How do you help people who claim to be open minded or even good christians or religious people but they are tolerant to others, other beliefs and are bias because of something?
Any thoughtful person convinced of what they believe must be in some respects (and often in many) very closed-minded and intolerant. How open-minded are you toward rape or murder, for example? Would you tolerate someone mixing a bit of rat poison into your favorite chocolate chip cookies? Are you open or closed-minded about 2+2 equaling 7? Would you tolerate a restaurant tallying up your dining bill while having an open-minded attitude about basic math sums not being fixed? Hopefully, you can see that in and of itself being closed-minded and intolerant is both common and necessary. As the saying goes, "A man who stands for nothing will fall for anything."
A Christian
ought to be very intolerant of a number of things: lying, fornication, false teachers and Gospels, gossip, perversion, arrogance, laziness, gluttony, denying the deity of Christ, the insufficiency of God's word, and so on. If your intent is to get believers to soften toward any of these things, you make yourself an enemy of God. He gives not the slightest bit of ground to sin and false belief. Neither should you - or other believers.
I had encountered intolerant atheists and agnostic who claim they are free thinkers and I find they are more intolerant than right winged conservative fundamentalists.
What do you mean by "right-wing, conservative fundamentalists"? I find people like to throw around these labels without having a clear idea of what they are referring to.
The most intolerant and murderous political regimes in the last 100 years or so were all atheistic ones. Mussolini, Stalin, Pol Pot, and Mao together murdered over a 100 million people! Never has intolerance been more severe and more destructive than when exerted by people who have forsaken God.