nod off vs snore

nod off

verb
  • To fall asleep, especially unintentionally. 

snore

verb
  • To breathe during sleep with harsh, snorting noises caused by vibration of the soft palate. 

noun
  • The act of snoring, and the noise produced. 

  • An extremely boring person or event. 

How often have the words nod off and snore occurred in a corpus of books? (source: Google Ngram Viewer )