Hi IpshitaSaha,
Raising a 600 to a 720+ will likely take at least another 2 months of consistent, guided study - if you could consistent score in the high V30s or V40s though, then you could find all of the missing points that you're looking for in the Quant section. With your current timeline, you would only have about 1.5 months of potential study time though, so you might need to consider pushing back your Test Date or changing your Score goal.
That all having been said, if it's been at least 2 weeks since you took that practice CAT, then we need to see a more recent performance (so we can assess whether your current 'way' of studying is leading to improvement or not).
1) When are you planning to apply to Business School?
2) What Schools are you planning to apply to?
3) Going forward, how many hours do you think you can consistently study each week?
GMAT assassins aren't born, they're made,
Rich