I have just tried this. I couldn't replicate the problem, using the exact same text you described. I tried in IE, Firefox and Opera.
Great. An intermittent problem. It's not failing for me either at this time. All I can think to do is to post to this thread again the next I see this failure.
FWIW, I don't think the browser used matters for this error. The "No topics met your search criteria" error message seems to indicate pretty clearly that it comes from the search engine on a site server, don't you think? Could it be caused by a lack of resources at times when the server load is high??
Thanks for trying to look into it.
-john