Can I search for rtf files containg @ in their title?

I don’t seem to be able to search for rtf files containing the @-symbol in their title… Is that correct or am I doing something wrong?

I’d like to have a smart group giving me all the quotes in the database. Rather than tagging every quote to indicate that it is a quotation rather than a note, I’d like the smart group to check whether the title contains @ (because I always indicate the page the quote comes from by way of an @ symbol).

Many thanks for your help!

I only just found this post. Apparently, DevonThink only recognizes alphanumerical symbols. I will thus have to tag all quotes accordingly.