Hi Alex,
I have the same issue on multiple Macs. Having said that, there MUST be an issue with the search. I've actually had it a long time, but I never go around to dealing with it. I have to go to my Windows computer most of the time to search my email.
The results I get are not complete. for example, I have a to do email to myself. when I search To Do, I get way to many results especially because I search for the subject only. The results to not even have "To Do" in the subject.
Also, my settings, search option does not have a reindex option. I actually looked for that before writing. I've been in IT since 1985 FYI. I'm not the average used, but this is a problem I can't solve.
What other thoughts do you have?
Rob