Boo vs Crow

Boo

name
  • The Boko language. 

  • A community in Nacka, Stockholm, central Sweden. 

Crow

name
  • The Siouan language of this tribe. 

  • A surname. 

noun
  • A member of a Native American tribe of southern Montana. 

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