Guys I need help..

As i have already read 4 books(PMBOK,RITA,HEADFISRT,ANDY CROW) Andy crow is in process rest of them twice..but when I am givin exam at the end of the chapter(Andy crow) I am scoring agin as 15/25,16/25,21/25...

I have just finished the chapter stakeholder managment and now will be studing how to pass PMP exam(chapter 14-Andy crow) but after giving exams fro Andy crow my nervous level has gone 60% up because i m scoring horribly bad..I have plan to schedule my exam on 21-July about 2 months left..