approve vs get behind

approve

verb
  • To consider worthy (to); to be pleased (with); to accept. 

  • To officially sanction; to ratify; to confirm; to set as satisfactory. 

  • To make profit of; to convert to one's own profit — said especially of waste or common land appropriated by the lord of the manor. 

  • To regard as good; to commend; to be pleased with; to think well of. 

get behind

verb
  • To appreciate, to enjoy. 

  • To support, to cheer on. 

  • To have a trip or any pleasurable experience with drugs. 

  • To come to believe something; to change one's mind into a new position. 

  • Used other than figuratively or idiomatically: see get, behind. 

How often have the words approve and get behind occurred in a corpus of books? (source: Google Ngram Viewer )