motor coach vs railway carriage

motor coach

noun
  • A powered railway vehicle, designed for passenger transport, capable to pull (or push) other railroad cars (compared to a railcar which only consists of a single railway vehicle with a driver's cab at both ends). 

railway carriage

noun
  • A railroad car (for passengers) 

How often have the words motor coach and railway carriage occurred in a corpus of books? (source: Google Ngram Viewer )