pull back vs sheathe

pull back

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

  • To retreat. 

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

  • To score when the team is losing. 

sheathe

verb
  • Of an animal: to draw back or retract (a body part) into the body, such as claws into a paw. 

  • To thrust (a sharp object like a sword, a claw, or a tusk) into something. 

  • To put (something such as a knife or sword) into a sheath. 

  • To encase (something) with a protective covering. 

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