It's just that as I see it as a non-Christian, I don't quite understand how some people can pick and choose what they think should be taken as it says, and other things should be seen as a more symbolic message.
I understand that it seems strange. The thing is, you can't understand Xianity by simply reading the Bible and hanging around with a few Xians--that method is fraught with problems of ego and culture, which end up clouding the real issues.
A better way to do it is by going to visit an Orthodox priest--that's what I did. Someone like you, who is asking searching questions, would benefit from this rich tapestry of knowledge that supports and explicates the Bible--this tapestry is called Apostolic Tradition. A lot of that knowledge is experiential and liturgical, but you need it in order to comprehend Xian practice.
A less effective way is to use the internet

simply because everyone is different, and a flowing dialogue is the quickest and least problematic way of finding an individual's root questions and answering them. Also, priests are usually learned men, and they have heard
all the questions you might have. I'm just a stupid layperson, what on earth do I know?
And it is true that the bible has several areas that are hard or almost impossible to translate form the greek due to the differences of the ancient and modern language.
Some areas are very hard to translate into English, particularly those in Greek. They're not impossible to
explain, though. I'm doing Bible study with an Egyptian-Greek monk, and he and I spend many happy hours discussing the original Greek.
and also due to the fact that the original copies of the scriptures that make up the bible don't exist anymore as they were written before paper was invented, and they had to write on leafs and animal skins, so miscopies are even possible.
This bothered me during my road to Xianity too. I asked the same questions and simply would. not. convert. until I was satisfied with that answers, so I get it. Please ask a priest--I am not fully qualified to answer this, since I'm not a scholar. I'll offer you what I remember from the explanation that satisfied me:
As you know, there are a variety of texts (Septuagint, Masoretic, Vulgate, etc.) that scholars cross-reference to create translations of the Bible. These are written versions of an oral tradition that were carried in all directions across Asia and the Near East for a few hundred years (i.e., before they were written down). And guess what? The written versions all match nearly perfectly. What does that tell you about the fidelity of the oral tradition? Well, it's near-perfect.
Linguists, too, will tell you that an original, earlier text exists "beneath" the gospels, which informs all of them. Slowly but surely they are piecing together that original using forensic linguistics. Happily, so far there are no contradictions (last I heard anyway).
Also, you know the small inconsistencies that occur in the Gospels in particular? Things like what Jesus' exact last words were. Now if people were effing around with the text, trying to make it "convincing" and so forth, they would have changed those details in a heartbeat. But they didn't. They kept the text bumpy and a little inconsistent, because that's how it came to them. The bearers of Xian oral history were painstaking in their efforts to remain true to what the original witnesses said, even when it was a little embarrassing, and could have easily been changed to save embarrassment.
There's a reason God prepared the Jews with thousands of years of scholarly tradition to carry Scripture into the world. Back then, Jewish boys memorised
the whole Torah and often parts of rabbinical writings too. They were even prepared culturally to believe that bearing false witness was a grievous sin. So they preserved an even more perfect oral tradition than most cultures would. (Side note: remember that many went to their deaths defending the truth of the tradition they were given. This wasn't something that they took on lightly.)
So as to questions to your post, because much of the bible is possibly mistranslated, how would you know what should be true and what is not? How would you know if Jesus actually did die on the cross to pay for man's sins, perhaps that was a mistranslation too? Is there scholarly evidence of some parts of the bible being more likely the real truth than others?
See my previous points, but besides that: you need to ask a scholar or priest these questions. I asked the same ones, and be comforted, there are intelligent answers for them, only I don't have a few days to compile the references I would need to show that to you.
The short answer is: the areas of the Bible that are difficult to translate, or which differ slightly across the various versions that I mentioned above, are not areas that deal with issues of salvation. They're things like "did Jesus really write in the dust before he spoke to the Pharisees that one time?", etc. Not things like "Did Jesus really die on the cross?" or "Did he die on the cross for a different reason to what we think he did?"
And about the bible being spiritual truth and not necessarily the physical truth. Is that what certain churches or denominations teach? Or are there many scholars that believe that? Or are there other reasons how we would know that the bible is the spiritual and not physicall truth?
I'm an Orthodox catechumen. I can't speak for every denomination, but certainly in Orthodoxy the teaching is that spiritual reality is the only 'true' reality, and that everything should be looked at through the lens of the soul.
Note: there's a chance that I don't understand your question. The concepts we're approaching here are very deep and complex, so please keep in mind that I many be misunderstanding you. I apologise if I have. Please ask a priest.
Here's an example that may clear up a little whether we are understanding each other correctly: I've been told that ancient saints' lives should be read as spiritual tales, given by God, that hold meaning on many levels. Every time you read them, something new emerges to nourish you. Because I'm a Xian, the Holy Spirit is infusing me as I read, constantly revealing new things.
So it doesn't matter that St George's dragon never walked on the Earth: God is speaking through symbolism of a higher spiritual reality--so the dragon may symbolise George's sinful impulses, which he defeats.
Conversely, if something did occur in the physical world, like a martyrdom, the saint's story is not trying to tell you that you'll only be a good Xian is you are physically martyred; God is calling you to martyr yourself
spiritually, to sacrifice your egotistical nature and trust him completely.
Please note, I am really a dumb***, so you need to ask a priest about this.
I've said it before and I'll say it again: the "literal-ness" or not of someone's interpretation of Scripture does not make them a good or bad Xian. If it did, it would make a severely retarded person, or a pre-literate child, in danger of hellfire.
"By their fruits will you know them": are they loving, joyful, peaceful, faithful, gentle, self-controlled, filled with loving-kindness, long-suffering, and all that jazz? That's how you judge a Xian, if you must make any judgement at all.