Allah has given knowledge to man according to his capacity in his/her time how much he understands ..like for moses( peace be upon him) he has given taurait(Torah) for jesus ( peace be upon him)Injeel ( bible)and for the last prophet mohammed ( peace be upon him)quran...torah has been changed by jews according to their fancies they too accept that they dont have the original torah as was reveled to moses and even christians after soo much presure agrees that bible has been changed but muslims belives and its a open prove that quran was never been edited from the day it came....about why Allah allow these changes is just becoz he dont care about that book anymore as new version is coming that why he left it open but for the quran the case was different coz Mohammed ( peace be upon him) is the final messenger of Allah and after that there will be no messenger and message from Allah he promised that he was protect it and for your information each book sended by allah approves the other books soo no need of old version as this new version is having all the information...it takes only little commonsense to understand this just go and research these books you will find lot similarities in all of them but quran is complete book of Allah ..he completed his favour on humans by sending us quran as the complete way of life...i use my complete brain now i advice u to use ur brain in Allah's way
