do a slow burn vs smile

do a slow burn

verb
  • To experience a gradually increasing feeling of anger or frustration; to slowly burn. 

smile

noun
  • Favour; propitious regard. 

  • A facial expression comprised by flexing the muscles of both ends of one's mouth, often showing the front teeth, without vocalisation, and in humans is a common involuntary or voluntary expression of happiness, pleasure, amusement, goodwill, or anxiety. 

verb
  • To have (a smile) on one's face. 

  • To express by smiling. 

  • To express amusement, pleasure, or love and kindness. 

  • To be propitious or favourable; to countenance. 

  • To look cheerful and joyous; to have an appearance suited to excite joy. 

How often have the words do a slow burn and smile occurred in a corpus of books? (source: Google Ngram Viewer )