code: public FindResults find(String id, ExternalSource externalSource, String language) throws MovieDbException {
          return tmdbFind.find(id, externalSource, language);
      }
docs: You con use this method to find movies, tv series or persons using
  external ids.
  
  Supported query ids are
  <ul>
  <li>Movies: imdb_id</li>
  <li>People: imdb_id, freebase_mid, freebase_id, tvrage_id</li>
  <li>TV Series: imdb_id, freebase_mid, freebase_id, tvdb_id,
  tvrage_id</li>
  <li>TV Seasons: freebase_mid, freebase_id, tvdb_id, tvrage_id</li>
  <li>TV Episodes: imdb_id, freebase_mid, freebase_id, tvdb_id,
  tvrage_idimdb_id, freebase_mid, freebase_id, tvrage_id, tvdb_id.
  </ul>
  
  For details see http://docs.themoviedb.apiary.io/#find
  
  @param id the external id
  @param externalSource one of {@link ExternalSource}.
  @param language the language
  @return
  @throws MovieDbException exception