dead-end vs fall back

dead-end

verb
  • To come to a dead-end. 

noun
  • A road with no exit. 

  • A position that offers no hope of progress. 

adj
  • Going nowhere; blocked. 

fall back

verb
  • To retreat. 

  • Used other than figuratively or idiomatically: see fall, back. 

  • To fail to fulfill a promise or purpose. 

How often have the words dead-end and fall back occurred in a corpus of books? (source: Google Ngram Viewer )