gnaw at vs torture

gnaw at

torture

noun
  • The intentional causing of somebody's experiencing agony. 

  • The "suffering of the heart" imposed by one on another, as in personal relationships. 

  • (often as "absolute torture") Stage fright; severe embarrassment. 

verb
  • To intentionally inflict severe pain or suffering on (someone). 

How often have the words gnaw at and torture occurred in a corpus of books? (source: Google Ngram Viewer )