down on one's luck vs snakebit

down on one's luck

adj
  • Unlucky or undergoing a period of bad luck, especially with respect to financial matters. 

snakebit

adj
  • Experiencing a period of bad luck; unlucky. 

  • Jumpy, as if expecting to struck by sudden misfortune. 

  • Bitten by a snake. 

  • being drunk and high at the same time. 

How often have the words down on one's luck and snakebit occurred in a corpus of books? (source: Google Ngram Viewer )