coalfish vs escolar

coalfish

noun
  • any of several blackish fish, especially Pollachius virens, a pollack, and Anoplopoma fimbria, sablefish. 

escolar

noun
  • Any fish of species Ruvettus pretiosus, oilfish. 

  • Lepidocybium flavobrunneum, one of the snake mackerels. 

  • Any of several other perciform fish of the family Gempylidae (snake mackerels). 

How often have the words coalfish and escolar occurred in a corpus of books? (source: Google Ngram Viewer )