I've found that part of the solution is to give it more to work with, and in a 'dumber' way. Remember, Google search isn't really a query language any more, it's more of an NLP find-what-I-mean interface. So sometimes instead of giving it keywords and logical operations ('beer +fridge -root -sassafras'), you can get better results by just asking a question ('get one of my beers from the fridge').