hijab vs keffiyeh

hijab

noun
  • A traditional headscarf worn by Muslim women, covering the hair and neck. 

  • The practice, among Muslim women, of covering the body after the age of puberty in front of non-related adult males. 

keffiyeh

noun
  • A headdress traditionally worn by some Arabs, also used as a scarf. 

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