Answer 1

You must modify your regular expressions to work, since in the current way they will not match. Your regular expressions should look like this:
hi = /h(i|ello|allo)/i;
wau = /Who\s(are|r)\s(you|u)\?/i;
whau = /What\s(are|r)\s(you|u)/i;
Edit: I had not seen all your code, since I saw it I thought that this would be more appropriate for the way you are working your RegExp:
hi = /h(i|ello|allo)/i;
wau = /[who(are|r)(you|u)\?]/i;
whau = /[what(are|r)(you|u)\?]/i;

Answer 2

I removed spaces in the regex expressions and it matched my input (without spaces, ofc). Perhaps there is a different way of expressing whitspaces there? Can't tweak around much ATM, but the problem is surely with the expression itself.

Answer 3

Did you try with the RegExp that I put later? They work for me
https://code.sololearn.com/W9AA93Fm2DZK