fracture vs unravel

fracture

verb
  • To break, or cause something to break. 

  • To amuse (a person) greatly; to split someone's sides. 

noun
  • A break in bone or cartilage. 

  • An instance of breaking, a place where something has broken. 

  • A fault or crack in a rock. 

unravel

verb
  • To become undone; to collapse. 

  • To separate the threads (of); disentangle. 

  • To become separated; (of something woven, knitted, etc.) to come apart. 

  • To separate the connected or united parts of; to throw into disorder; to confuse. 

  • To clear from complication or difficulty; to unfold; to solve. 

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