concern oneself vs sweat out

concern oneself

sweat out

verb
  • To endure or go through (an ordeal). 

  • To accomplish or achieve, usually through endurance or effort. 

  • To sweat; to secrete sweat because of heat, nerves etc. 

How often have the words concern oneself and sweat out occurred in a corpus of books? (source: Google Ngram Viewer )