mystery tour vs saunter

mystery tour

noun
  • A short-duration outing by coach to a destination that is not revealed in advance 

saunter

noun
  • A leisurely pace. 

  • A leisurely walk or stroll. 

verb
  • To stroll, or walk at a leisurely pace. 

How often have the words mystery tour and saunter occurred in a corpus of books? (source: Google Ngram Viewer )