flinch vs slip through the cracks

flinch

verb
  • To dodge (a question), to avoid an unpleasant task or duty 

  • To make a sudden, involuntary movement in response to a (usually negative) stimulus; to cringe. 

  • To let the foot slip from a ball, when attempting to give a tight croquet. 

noun
  • The slipping of the foot from a ball, when attempting to give a tight croquet. 

  • A reflexive jerking away. 

slip through the cracks

verb
  • To escape notice or lack sufficient attention. 

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