knock on wood vs throw out

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. 

throw out

verb
  • To discard; to dispense with something; to throw away. 

  • To offer an idea for consideration. 

  • To dismiss or expel someone from any longer performing duty or attending somewhere. 

  • To produce in a haphazard fashion. 

  • To emit. 

  • To cause or experience debilitating muscle or joint pain in (a body part). 

  • To put into a state of confusion. 

  • To cause to project. 

  • To utter carelessly. 

  • To outdistance; to leave behind. 

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