Bug 1055435 (All text search with RDBMS backend does OR
instead of AND) is fixed in 0.7.10/0.7.11.

However, the *title* search still does OR instead of
AND (at least with pysqlite backend).

This behavior is inconsistent with the full text search
and also has the effect that the title search may
return a lot more results than the full text search for
the same search string.