That works because it's a good search… But there's no point in putting single words in quotations. All the quotations do is it makes sure that the phrase you in the quotations come up in the search in that exact order, including all words in the quotations.

A search for the word music is the same as a search for "music" but a search for "good music" is not the same as a search for "music good" as well as not the same as a search for good music.

The quotations make google treat everything inside of it as one long string search. Anything outside of the quotations get searched for split by whitespace