toil vs work one's fingers to the bone

toil

verb
  • To work (something); often with out. 

  • To struggle. 

  • To labour; work. 

  • To weary through excessive labour. 

noun
  • Trouble, strife. 

  • Labour, work, especially of a grueling nature. 

  • A net or snare; any thread, web, or string spread for taking prey. 

work one's fingers to the bone

verb
  • To work especially hard, usually for an extended period. 

How often have the words toil and work one's fingers to the bone occurred in a corpus of books? (source: Google Ngram Viewer )