bug out vs pass unnoticed

bug out

verb
  • To abandon someone without warning. 

  • To miss school, play truant, play hooky. 

  • To crash or glitch. 

  • To leave (a place) hastily. 

  • To freak out, to go crazy, e.g. from worry. 

  • To cause to bulge. 

noun
  • A rapid retreat, a rout. 

pass unnoticed

verb
  • To not be noticed. 

How often have the words bug out and pass unnoticed occurred in a corpus of books? (source: Google Ngram Viewer )