How many times did you read Rita's book? Most people read it AND the PMBOK Guide at least twice.
How many practice test questions did you take? Many people take thousands. (You can easily find thousands of free PMP practice questions on the web, although many are outdated and few will be up-to-date after July 31. CAPM questions are much harder to find.)
When you took the practice tests, did you research the answers you got wrong? Did you research the answers you had to guess at? Memorizing will only get you part way through PMI's tests; you need to dig and understand the material.
If you are taking the CAPM, you must want to become a PMP. Consider studying for the PMP exam. The deeper knowledge will give you understanding that goes beyond mere memorization for the CAPM exam. Also, for the PMP exam, you need to have 35 contact hours. Again, the extra effort would help you with the CAPM exam.
The two books I've heard the best reports about are Rita's books and the Head First books. You can also find many free podcasts on the web and on iTunes.
Two names to look for are Oliver Lehmann and Cornelius Fitchner. Oliver has some free apps and the best sample question on the web. Cornelius has some great 'casts, some of which are free.
Finally, when you have a tough time with some concept or a sample exam question, feel free to ask about it in the Google+ group, "Project Management, PMI, PMP Certification." Ask under the tab "PMP preparation questions." (Out of respect for copyrights, please identify the source of quotes.)
Other than that, I suppose there's not much you can do.
Copyright 2013, Richard Wheeler -- Permission granted for non-profit or personal use with a link to this post.