Hello, Bonojit. You appear to have made a rookie mistake in blowing through the OG without making any significant improvement, although I cannot be sure what your GMAT™ goals may be. Volume does not equal progress. You should have taken the time to study the explanations to your incorrect answers as often as you were making them, thereby setting yourself up for success on similar questions down the road. But hindsight is 20/20, right?
Your accuracy on repeat questions may not reflect your current understanding of the material, since you have seen the questions so recently and may have made a mental note of the correct answers (even if you are unaware of it). The best way to move forward would not be so much to keep going through the same questions, but to take on new ones. You can try questions from the GMAT Advanced bank, for instance, although, as the name implies, many of the questions are not easy, and you would not want to exhaust an additional resource before you might be up to the task. Your mocks suggest you need to put in some serious time unlocking Easy and Medium questions.
There are other study packs of questions you can get through mba.com, although the same questions can be found in the forum if you know how to look for them. (I would not want to spend the time sifting through official questions from OGs and those from other, non-GMAT Prep sources and figuring out how to tease them apart.)
I cannot emphasize the review process enough. Look up the questions you have missed in the forum and see if some of the explanations make sense to you, particularly those that explore the wrong answers to Verbal questions. Then, to increase your mental stamina, you will want to grow accustomed to tackling more questions at a time, maybe starting with a set or two of ten questions, gradually working up to twenty, then thirty. This process can take weeks.
Finally, you can try your hand at third-party questions, such as those by
Manhattan Prep or Veritas Prep, but they should not serve as a substitute for official material.
Good luck with your studies.
- Andrew