heat up vs piff

heat up

verb
  • To become more exciting or intense. 

  • To heat, to cause to become hotter. 

piff

verb
  • To throw something vigorously. 

intj
  • An exclamation of annoyance or contempt; pish; pshaw. 

adj
  • good or attractive. 

noun
  • Piffle; nonsense; rubbish. 

How often have the words heat up and piff occurred in a corpus of books? (source: Google Ngram Viewer )