The RR-Line's search utility is a bit quirky, but if you know how to use it it works very well.
1) If you are going to search an entire message, you must limit your search to only one forum at a time. If you don't, the function will time out and you will get an error message.
2) The best way to use the search is to search by Subject Only. When searching this way you can search all the forums at once.