Blacky vs Sambo

Blacky

name

  • A nickname of the surname Black. 

Sambo

name

  • A nickname from the given name Samuel. 

  • A nickname from the given name Samantha. 

  • A Russian martial art and combat sport. 

noun

  • A black person, especially one who is accommodating or servile towards whites; an Uncle Tom. 

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