Search last 7 days in facebook search api

Question

I need a solution in graph api or fql to search a specific keyword for last 7 days or a way to count the no of total search results.

Right now,

I am applying a heavy limit. It works if result is single page, but fails on pagination.

http://graph.facebook.com/search?type=post&q=wonders&since=2012-01-13&limit=99999999999999

I want to gather data for statisticall purposes.