look around vs pop in

look around

verb
  • To search a place. 

  • Used other than figuratively or idiomatically: see look, around. 

  • To take note of what is going on; to make oneself aware. 

  • To turn one's head to see what is behind oneself. 

  • To inspect a building or area. 

pop in

verb
  • To pay a visit in an impromptu manner. 

How often have the words look around and pop in occurred in a corpus of books? (source: Google Ngram Viewer )