Use whatever method you find most effective. I'm partial to using the built-in search, as it is easier to limit your query to tag categories using the
For example to require that the result be in the php tag:
[php] expects parameter 1 to be resource boolean given
... thousands of duplicates appear...
Occasionally I'll be looking for one of my own previous answers, wherein the
user:userid syntax is quite handy. Obviously this is less useful for finding others' answsers in a targeted way unless you first visit their profiles to find their userids.
[php] user:541091 expects parameter 1 to be resource boolean given