I am looking for a question or answer i had provided, but i couldn't find it on superuser. I guess it was moved somewhere else (i.e. stackoverflow).
How can I search such answers/questions?
If the question has been migrated, then the corresponding answer(s) will be deleted, so there's no way to search that.
You would probably have to search with the question title/keywords, something like closed:1 <question title/keywords>
user:me closed:1
in the search box. I'm not sure if it will work for finding answers; but if a question was migrated it will be closed, so this should pick it up (unless it was deleted after the migration...).