You should know that just because you cant find the word "trinity" in the Bible doesnt mean that the Trinity doesnt exist. Just because you cant fully comprehend the Trinity doesnt mean that there isnt one.
Can you comprehend fully, "Christ in you?" Of course you cant. Thats why Paul calls that a "mystery," in Col. 1:27. Can you comprehend that you are a member of Christs body, "of his flesh and of his bones?" Of course you cant. Thats why Paul calls that a "mystery," in Eph. 5:30-32. Likewise, the Trinity is a mystery, but it is well established in the Bible and in type.
A good place to look for the Trinity is in the name of God. Jesus told his disciples to baptize "in the name of the Father, and of the Son, and of the Holy Ghost," (Matt. 28:19). So, in the Bible we should be able to locate one name by which all three persons are called. That name is the Lord. In Eze. 20:5, 19, 26, 38, 42, and 44, we find that the name of God the Father is the Lord. In Phil. 2:11 and 1 Cor. 12:13, we find that the name of Jesus Christ is the Lord. And in 2 Cor. 3:17, we find that the name of the Holy Spirit is the Lord. So, when Cornelius and his household were baptized in the name of the Lord (Acts 10:48), the command of Jesus Christ in Matt. 28:19 was fulfilled.