I use the searching without AND.
i describe AND because this is a normal syntax in queries.
When I use searching without AND the result is sometimes wrong.
Example > searching with bad experience
Result > Bad behavior in …, Good experience over …
Sorry, now I see what you mean. A limitation in the Search feature, apparently. I would have expected to be able to use quotation marks. You could use the separate Find command, but it would probably be too clumsy, as you will only find the matches one at a time.
If I understand you correctly, it’s not boolean search operators you are interested int, but the possibility to search for strings. If you accept the clumsiness of getting only one match at a time, you could use the Find command (instead of Search) in the Edit menu. You could even find patterns, using regular expressions, there.
Another option would be to tag your tasks with ”Good behavior”, ”Bad behavior” and so on.