Say I wanted to find blogs where there were recent comments approved, would I just be adding something like the following?:

"December 20th, 2011" + "X" + "Y" + "Z"
"December 21st, 2011" + "X" + "Y" + "Z"
"December 22nd, 2011" + "X" + "Y" + "Z"
"December 23rd, 2011" + "X" + "Y" + "Z"
"December 24th, 2011" + "X" + "Y" + "Z"
"December 25th, 2011" + "X" + "Y" + "Z"


I feel like when I scrape like this I don't get blogs with recent comments.

So I guess my question is what would be that "part" of the footprint to filter blogs that have had recent comments posted?

Thanks in advance.