Senga vs charva

Senga

noun

  • A female "ned". 

name

  • A female given name originating as a coinage, of mainly Scottish usage. 

charva

noun

  • Unruly youth; disobedient child or teenager. 

  • Friend; mate. 

  • A chav. 

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