Hi Mahesh,
In Webi Add the same query twice and apply the filters separately and use merge dimension to combine both the query.
For Eg : Query Z_TEST_QUOO1
Add the query Z_TEST_QU001 twice and add first filter on " '2012-05-01' to '2014-04-30'" and second filter on query2 " 2011-05-01' to '2014-04-30'".
Thanks,
Shakthi Raj Natarajan