cold storage vs cooler bag

cold storage

noun
  • Refrigerated storage. 

  • A place where private keys are stored away from the Internet to prevent them from being stolen. 

  • A state of postponement; the back burner. 

cooler bag

noun
  • Insulated bag used to keep food items cool for a limited amount of time (for example on the way from a grocery store to one's house). 

How often have the words cold storage and cooler bag occurred in a corpus of books? (source: Google Ngram Viewer )