It is not currently possible to enter a non-breaking space (Ctrl+Shift+Space) in the Editor's search function. If I search for a phrase which has a non-breaking space in it, Studio will not find it unless I use a star symbol (Two*words). In this scenario, it would of course not find ordinary spaces.
I initially reported this as a bug and was told that the search function is a basic function which is not designed to cope with this sort of thing. I therefore suggest that the search function should be programmed to find all types of space and not to "discriminate". This is how Microsoft Word works.
The search function is primarily a linguistic function and, by definition, the translator does not always know what he/she is searching for. It is better to find too much than to be at risk of missing something.