Revising return

I am assuming you are asking about income tax return. Income tax return can be revised only if original return was filed within due date.

A ITR can be revised any number of times within 2 years from the end of relevant assessment year. For e.g. ITR duly filed of AY 2016-17 can be revised n number of times till 31st March 2018. Revision is allowed only if ommission was uninentional.

It is  not adviseable to revise your return too many times since it may attract scrutiny