earn one's crust vs prosper

earn one's crust

verb
  • To earn money, to do something as a job. 

prosper

verb
  • To be successful; to succeed; to be fortunate or prosperous; to thrive; to make gain. 

  • To grow; to increase. 

  • To favor; to render successful. 

How often have the words earn one's crust and prosper occurred in a corpus of books? (source: Google Ngram Viewer )