Find hardcoded strings but not those for file names (Xcode, Regex help)
You can use a negative lookbehind to exclude those cases:
(?<!(imageNamed:|NSLog\())@"[^"]+"
For Swift project
In Xcode > Search > Find > Regular Expression -- type "[a-zA-Z0-9]+"
I think this would be more comprehensive
"[a-zA-Z0-9 ?!.,;/\-=+)(*&%#@]+"
Search > Find > Regular Expression -- type