other side vs spiritual world

other side

noun
  • The afterlife, as a supernatural realm inhabited by spirits of deceased people. 

  • Used other than figuratively or idiomatically: see other, side. 

spiritual world

noun
  • The afterlife. 

  • A metaphysical plane of existence parallel to the material world and occupied by spirits and other unearthly forces. 

How often have the words other side and spiritual world occurred in a corpus of books? (source: Google Ngram Viewer )