Chinese foot vs chek

Chinese foot

noun
  • A chi, a traditional Chinese unit of distance based on the human forearm, now standardized variously as (Mainland China) ¹/₃ or (Taiwan) ¹⁰/₃₃ of a meter. 

chek

noun
  • A Hong Kong foot. 

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