look down on vs pooh-pooh

look down on

verb
  • To regard or treat as inferior. 

  • To view [people or events on Earth] from the vantage point of the afterlife (originally, Heaven) 

pooh-pooh

verb
  • To dismiss idly with contempt or derision. 

How often have the words look down on and pooh-pooh occurred in a corpus of books? (source: Google Ngram Viewer )