Muslim vs towelhead

Muslim

noun
  • A person who is a follower and believer of Islam. 

adj
  • Being or relating to a believer of Islam. 

towelhead

noun
  • A member of the Muslims, Arabs, Sikhs, and other groups that traditionally wear headdress such as a turban and keffiyeh or headscarf. 

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