You can use git log to search when a given string matches an entry in there and also see from which branch/tag they matched a...

You can use git log to search when a given string matches an entry in there and also see from which branch/tag they matched and even see the patch inline by using git log -S 'string-for-match' --source --all -p. -S is used to provide the search string, --source --all will properly format ref names to their respective source branch/tag and -p will allow you to see the patch inline. The last flag can be omitted if one just wants to see the list of commits and could go through each one individually by grabbing their hash and using a git show command afterwards. See for more