I don't see why it wouldn't work with spaces or \s. It should. But to answer the question you asked in general terms, the way to match exact phrases in a regex is to surround them with \Q and \E:
/\Q<phrase 1>\E|\Q<phrase 2>\E|\Q<phrase 3>\E/
That's normally used for text that contains escapes or regex metacharacters. You really shouldn't need that for spaces.