protected function paramSearchMeta( array $search ) {

		// Book Metadata
		$request_metadata = new \WP_REST_Request( 'GET', '/pressbooks/v2/metadata' );
		$response_metadata = rest_do_request( $request_metadata );
		$book_metadata = $response_metadata->get_data();
		if ( $this->keyValueSearchInMeta( $search, $book_metadata ) ) {
			return true;
		}

		// Chapter Metadata
		$request_metadata = new \WP_REST_Request( 'GET', '/pressbooks/v2/toc' );
		$response_metadata = rest_do_request( $request_metadata );
		$toc = $response_metadata->get_data();
		foreach ( $toc['front-matter'] as $fm ) {
			if ( $this->keyValueSearchInMeta( $search, $fm['metadata'] ) ) {
				return true;
			}
		}
		foreach ( $toc['parts'] as $p ) {
			foreach ( $p['chapters'] as $ch ) {
				if ( $this->keyValueSearchInMeta( $search, $ch['metadata'] ) ) {
					return true;
				}
			}
		}
		foreach ( $toc['back-matter'] as $bm ) {
			if ( $this->keyValueSearchInMeta( $search, $bm['metadata'] ) ) {
				return true;
			}
		}

		return false;
	}