Hello Aspirant

If this is a question related to a previous question then can you please ask this question in the comments section of the previous question. This would help us in understanding the context of the question.

If this is a generic question and I were to give a generic answer, then there are certain books that you can read that will help you succeed - 

• Manorama

This would increase your GK and awareness

• Basic Mathematics

This always comes handy

• Classic novels such as 1984, Animal Farm etc

These novels improve your English and also improve the way you process comprehensions

Best Of Luck!