We would love to make suggestions! We need more info from you though.
Did you take all of these tests under official testing conditions? Did you do the essays? Did you take only two 8-minute breaks between sections? If you deviated from official conditions in any way, tell us how (and for which tests).
Second, you've taken 5 tests now that have had very close to the same scores (really the only outlier score was the one 37 on verbal). When did you take these tests? I'm concerned that you may not be doing enough between tests or may be taking the tests too frequently.
CAT exams are really good for (a) figuring out where you're scoring right now, (b) practicing stamina, and (c) analyzing your strengths and weaknesses. The actual act of just taking the exam is NOT so useful for improving. It's what you do with the test results / between tests that helps you to improve.
Okay, now on to your request for study suggestions. Do the analysis described in the below article on your last MGMAT practice test (or, if that one was done under very non-official conditions, the one before that):
http://www.beatthegmat.com/a/2009/09/23 ... tice-testsThen come back here and summarize your analysis for us. That will give us the concrete data we need in order to give you some targeted advice.