Searching the IFS using Windows7

I just got upgraded to WIN7-Pro here at the office.

On occasion I have to search for a data string in files in folders in my
IFS, some of which have over 10000 files in them, and all I may have is a
name and approximate date the file was created. In XP-Pro this was easy as
cake. But in WIN7, today I had to do my first search to ensure we really
received a file, but the WIN7 search couldn't find the file. I was able to
eventually find it manually (by looking in every file received for the last
three days).

Is there something I'm missing about how to search for a string in a file
in a particular folder?

Any good articles about how to use search in W7?