bust ass vs give it one's best shot

bust ass

verb
  • To work hard, especially when trying to achieve a goal. 

  • To fart. 

give it one's best shot

verb
  • To make one's best effort or attempt; to try as hard as possible. 

How often have the words bust ass and give it one's best shot occurred in a corpus of books? (source: Google Ngram Viewer )