toughen up vs work over

toughen up

verb
  • To make or become mentally tougher. 

work over

verb
  • To subject (a person) to a severe scolding, interrogation, etc. 

  • To physically attack in order to cause injury. 

  • To improve a prototype, or first draft. 

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