knock on wood vs provide

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. 

provide

verb
  • To act to prepare for something. 

  • To make a living; earn money for necessities. 

  • To give what is needed or desired, especially basic needs. 

  • To furnish (with), cause to be present. 

  • To make possible or attainable. 

  • To appoint to an ecclesiastical benefice before it is vacant. See provisor. 

  • To establish as a previous condition; to stipulate. 

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