raghead vs towelhead

raghead

noun
  • A Muslim, Arab, Hindu, Sikh, Indian or member of any group that traditionally wears a headdress such as a turban, keffiyeh or headscarf. 

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 raghead and towelhead occurred in a corpus of books? (source: Google Ngram Viewer )