You're right here:
but the results should have come up in the whole phrase search because that exact whole phrase exists
Nothing was found, because there was a dot at the end of the sentense you're trying to look up. I've fixed that, and now it should work.
I agree there could be some things fixed in search function. Programming it correct way, it's impossible to know about all possible cases. That's why you're welcome to describe such kind of errors on our forums, and we will say "thank you" for that.
Anyway, what we are providing, is not a search crawler here. You can do a basic search by various kind of methods, and it is enough in 99% of cases. What about 1% left? We just don't worry about it.
Installing Google search will be very intuitive for your users ;-) We also are planning to install it in the future.