Quoting the phrase seems to work, up to a point. "phpmyadmin error #1396" gives me
The following words are either very common, too long, or too short and were not included in your search:
"phpmyadmin error #1396"
Not altogether helpful. "error #1396" returned no results, and "phpmyadmin error" returned a long list, which at a quick glance did seem to refer to phpmyadmin errors, so it's a start.
I tried it using a two-word phrase from a post I just made. Unquoted, I get 18 pages of results; quoted, I just get my recent post. Pretty good, I thought. :)