Hi davidsubedi007,
Most Test Takers spend 3 months (or more) of consistent study time before they take the GMAT, so it might be that you just have not put in enough study time yet.
You did not mention much in the way of specific details in your post, so I'd like to know a bit more about how you've studied so far:
1) What materials have you used during your studies?
2) How have you scored on each of your practice CATs (including the Quant and Verbal Scaled Scores)?
3) When are you planning to take the GMAT?
4) What is your goal score?
GMAT assassins aren't born, they're made,
Rich