nobody vs sad sack

nobody

noun
  • Someone who is not important or well-known. 

pron
  • Not any person; the logical negation of somebody. 

sad sack

noun
  • An incompetent or inept person. 

  • A perennial failure or victim of misfortune. 

How often have the words nobody and sad sack occurred in a corpus of books? (source: Google Ngram Viewer )