knock on wood vs muse

knock on wood

verb
  • To take a customary action to ward off some misfortune that is believed to be attracted by a presumptuous statement. 

intj
  • Hopefully; a self-directive to undertake the customary action to ward off bad luck. 

muse

verb
  • To say (something) with due consideration or thought. 

  • To wonder at. 

  • To become lost in thought, to ponder. 

  • To think on; to meditate on. 

noun
  • A source of inspiration. 

  • A gap or hole in a hedge, fence, etc. through which a wild animal is accustomed to pass; a muset. 

  • An act of musing; a period of thoughtfulness. 

How often have the words knock on wood and muse occurred in a corpus of books? (source: Google Ngram Viewer )