Report brings objects from both sql's

I have Webi report that has union in it, the issue I am having is my report bring in objects from both the sql's into the report.Eg: Q1-- has A1,B1,C1,D1

and Q2--has A2,B2,C2,D2. The report bring all A1,B1,C1,D1and A2,B2,C2,D2, instead of A1,B1,C1,D1

How would I over come this issue? IS this because of not setting contexts .properly in the universe? Any suggestions will be helpful.