pull back vs turn tail

pull back

verb
  • To retreat. 

  • To pass (the ball) into a position further from the attacking goal line. 

  • Used other than figuratively or idiomatically: see pull, back. 

  • To score when the team is losing. 

turn tail

verb
  • To turn away from someone or something, in preparation for running away; to reverse direction; to leave or flee. 

How often have the words pull back and turn tail occurred in a corpus of books? (source: Google Ngram Viewer )