Solaris are you talking about the search bar inside "Choose Tags for Your Discussion" modal ? I can search for tags like "3D printer" just fine on my beta 12 forum. I also don't see anything that wouldn't play nice with spaces in the source code https://github.com/flarum/tags/blob/master/js/src/forum/components/TagDiscussionModal.js#L146
If that's indeed the thing you are having issues on, could you try disabling some other third-party extensions to see if the issue goes away ?
EDIT: oh I must have misread the report. The way it's currently implemented, you can only search from the start of the name. So "3D", "3D p" will work, but "printer" will not return anything. It's true that's it's not ideal, but that's the current implementation ☹️