nunchaku vs shortsword

nunchaku

noun
  • The skill of using this weapon in martial arts. 

  • A weapon originating from Okinawa, Japan, consisting of two sticks joined by a chain or cord. 

shortsword

noun
  • A sword of a class generally shorter than one meter, but longer than a dagger. 

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