How much did you prepare the first time around? You should have been able to identify your weak areas first through the GMAT CAT diagnostic test. From there, you focus on improving specific areas - you should seen ahead of time your weakness in CR and RC. If so, you should seek resources to help you improve in this area.
For CR: Try a sample CR question here: http://www.gmatpill.com/gmat-practice-t ... stion/1171
If you have questions, just leave a comment and we'll try to get to it.
For RC: Try some of the video strategies for RC and see how the thinking process compares to your own. http://www.gmatpill.com/practice-questi ... -guide-rc/
1.5 months is just enough time if you know how to allocate your time and focus in on studying in the right manner to improve your score. Private tutoring is also an option - you can look in your area. Be careful which tutor you get - the prices can easily skyrocket and you may not necessarily find them effective if you don't which one to go to.
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Zeke Lee, GMAT Pill Study Method (Study Less. Score More.)
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