Currently search backends but phpBB native handles hyphen in a way that it is ignored when there're no or there're wrapping spaces, e.g. `welcome-phpBB3` is equal to `welcome - phpBB3` and is equal to `welcome phpBB3` search query.

But for phpBB Native search backend `welcome - phpBB3` is getting turned into `welcome -phpBB3` which is completely different because it excludes phpBB3 so the final search result changes fully.

Handling of hyphen by search backend should be consistent on phpBB level.