Hi VANUKURIPAVAN,
There are a variety of different study materials that you could use to improve your SC skills, but it's not clear right now whether that's the only Verbal area that you need to work on or not. With a V28 (the Verbal Scaled Score that you listed in your profile from your 2nd Official GMAT), you would have lost significant points in ALL 3 major Verbal categories (RC, SC and CR).
Before I can offer you the specific advice that you’re looking for, it would help if you could provide a bit more information on how you've been studying and your goals:
Studies:
1) On what dates did you take each of your Official GMATs?
2) How long have you studied in total? Over the last 3 months, many hours have you typically study each week?
3) What study materials have you used over the course of all of your studies?
4) On what dates did you take EACH of your CATs/mocks and how did you score on EACH (including the Quant and Verbal Scaled Scores for EACH)?
Goals:
5) What is your overall goal score?
6) When are you planning to apply to Business School and what Schools are you planning to apply to?
You might also choose to purchase the Enhanced Score Report for your most recent Official GMAT. While the ESR doesn’t provide a lot of information, there are usually a few data points that we can use to define what went wrong on Test Day (and what you should work on to score higher). If you purchase the ESR, then I'll be happy to analyze it for you.
GMAT assassins aren't born, they're made,
Rich