await vs knock on wood

await

verb
  • To serve or attend; to wait on, wait upon. 

  • To expect. 

  • To wait; to stay in waiting. 

  • To watch, observe. 

  • To wait for. 

  • To be in store for; to be ready or in waiting for. 

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. 

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