eat away at vs scritch

eat away at

verb
  • To consume or use up, erode or wear away gradually. 

  • To erode. 

  • To cause to feel uneasy, troubled, worried, guilty, or vexed; to bother about something. 

scritch

verb
  • To scratch so as to relieve an itch or irritation. 

  • To make a light scratching sound, like a small animal burrowing. 

noun
  • The act of scratching an itch. 

  • A light scratching sound, like a small animal burrowing. 

How often have the words eat away at and scritch occurred in a corpus of books? (source: Google Ngram Viewer )