Hi Nitesh,

Reading Comprehension will seem to be a tricky one in most exams, but with practise you can easily tackle them.

First of all, vocabulary is very important. There are so many words and you don't have to know the meaning of all of them. However, there are a set of words that are repeated in all exams- like GRE, CAT, GMAT. You have to get a hold of them. There are many apps like Magoosh, Prep 4 GRE that can help.  

You also need to improve your reading speed. This can come from inculcating reading habit in your daily life. If you find reading novels/newspapers are boring, you can start from any area of your interest like fashion blog/ movie criticisms. The point is you have to be able to read many words in a short span of time.

Also, since RCs in competitive exams are from a wide diversity of topics, it will help if  you try to be interested in all walks of life. While attempting RCs, read them thinking that you are learning interesting stuff, instead of focussing on getting it right. 

Finally the most important point is that you need not answer all RCs. Competitive exams are all about selecting the right questions and getting them right. So, select the right RC questions and spend enough time on them to get it right.

Hope it helped, feel free to contact for any other queries.

All the Best!!