autorickshaw vs four-wheeler

autorickshaw

noun
  • A motorized rickshaw of South Asia and East Asia, often available for hire in the manner of a taxi. 

four-wheeler

noun
  • A horse-drawn hackney cab with four wheels, as opposed to a hansom or dogcart. 

  • Any vehicle with four wheels. 

How often have the words autorickshaw and four-wheeler occurred in a corpus of books? (source: Google Ngram Viewer )