put off vs slip through the cracks

put off

verb
  • To distract; to disturb the concentration of. 

  • To procrastinate. 

  • To emit; to give off (an odor, smoke, etc.). 

  • To cause to dislike; to discourage (from doing). 

  • To delay (a task, event, etc.). 

adj
  • daunted or fazed 

  • offended, repulsed 

slip through the cracks

verb
  • To escape notice or lack sufficient attention. 

How often have the words put off and slip through the cracks occurred in a corpus of books? (source: Google Ngram Viewer )