* Deletes all query-based words from the suggest index.
     *
     * @return true if the operation was successful, false otherwise.
     */
    public boolean deleteQueryWords() {
        final SuggestDeleteResponse response = suggester.indexer().deleteQueryWords();
        if (response.hasError()) {
            logger.warn("Failed to delete query words.", response.getErrors().get(0));
            return false;
        }