If you Search for Apps on the Google Play store you probably get results with many low rated Apps along with High rated Apps in the middle, Google is a search company is the first place so they decided to do something about it. Google just added a new filter to the web play Store that lets you restrict results to only those apps with 4 or more stars. That should clear out a lot of the junk.
The new filter is in a dropdown at the top of the screen when you limit searches to apps only (Games too). Just click the "4 stars +" option in the rating dropdown and you're done. Maybe more rating categories will be added later, but this is probably the most useful.
I can't think of many instances I'd want to include apps that get less than 4 stars in a search. Head to Google Play Website and try it out.