boyo vs cobber

boyo

noun
  • A stereotypically Welsh form of address for a man, usually younger than the speaker. 

  • A boy or lad. 

cobber

noun
  • A pal, buddy, mate, friend; often used in direct address by one male to another. 

  • A sweet consisting of a small block of hard caramel covered in chocolate. 

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