Here's a tip inspired by a question from Ethan Lipman, an active Gmail Chat user. He wants to be able to search his Gmail messages for key words, but the Search Results often return hits from his Chat session logs. Read on to find out how to simply exclude Chat session logs from your Search Results....
The solution turns out to be really simple, but not necessarily obvious. It appears that all Gmail Chat session logs are simply standard messages Labeled with a hidden Label of "Chat". So this means that many functions you use on Labels should work.
So, to exclude all Chat session logs from your Search Results, add the following text to your search string:
Likewise, if you wanted to include words found ONLY in Chat session logs, just add the following to your search string:
...making sure that it is the only "label:" string (unless you also want to include other Labels.)
Thanks to Ethan Lipman for the question!