How can I search within my own questions?
How to search only within my questions on SO?
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Under the Advanced Super Ninja search options, it mentions being able to use:
I put your user id number in there and you should only get questions you have posted in with that in your search terms. You can also apply this is to any user id and get all question only by a certain user.
And Dominic Rodger reminds us of the shortcut also: