If the bible truth is so powerful then why isn't it working better?

The Bible is doing what it is supposed to. It is sifting the wheat from chaff. When all is said and done, there will be a faithful kingom of glorified saints to serve God, just as there is a kingdom of sinner saints to serve him now. The world hates God, by and large, so there will be no peace like you are talking about until time is done. Jesus even said he didn't come to bring peace, but that believing in Him would bring division. That you see, and there are more pagans than Christians in the world. So it isn't God, His plan, or His Word that is failing, it is the Gods, plans, and imaginations of earths rebellious population that you are seeing, and that God has always seen (thus necessitating Christ's coming).