draw blood vs vitiate

draw blood

verb
  • To have an injurious effect; to strike home, as a barb or insult. 

  • To wound one's opponent in such a way that they bleed. 

vitiate

verb
  • To make something ineffective, to invalidate. 

  • To debase or morally corrupt. 

  • To spoil, make faulty; to reduce the value, quality, or effectiveness of something. 

How often have the words draw blood and vitiate occurred in a corpus of books? (source: Google Ngram Viewer )