differ vs straighten up

differ

verb
  • Not to have the same traits or characteristics; to be unalike or distinct. 

  • To have diverging opinions, disagree. 

  • To be separated in quantity. 

noun
  • A program that diffs, a diff. 

straighten up

verb
  • to start living a reformed life 

  • to sit up straight, to stop hunching. 

  • to steer straight 

  • to tidy; tidy up 

  • to deal with; put in order 

  • To become straight, or straighter 

  • To clarify 

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