[quote="Eshaang"]Hi,
I have already joined group calsses for GMAT preparation.
Although to practice more, I would like to which book or question bank I can use to help me practice and solve difficult questions to score more?
Few places I have read about Manhattan 800 or Kaplan 800. Other places even official review books by Wiley's were mentioned.
I only want questions and not looking for mock tests.
I am only look for higher difficulty question bank on each topic.
/quote]
If you are willing to go outside of the usual GMAT-related materials, try subject-related questions in dedicated Math and English classes and their respective tests. By practicing on different materials, you can build confidence.
GMAC has come out with official "difficult" questions which you can purchase online. Please check mba.com official site.