knock someone out vs overwhelm

knock someone out

overwhelm

noun
  • The state or condition of being overwhelmed. 

verb
  • To overpower emotionally. 

  • To cause to surround, to cover. 

  • To engulf, surge over and submerge. 

  • To overpower, crush. 

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