private function sql_search() {

		$sql = '';

		if ( $this->get( 'search' ) ) {

			global $wpdb;
			$sql .= '  AND (
                   m_last.meta_value LIKE %s
                OR m_first.meta_value LIKE %s
                OR u.user_email LIKE %s
            )';

		}

		if ( $this->get( 'suppress_filters' ) ) {
			return $sql;
		}

		/**
		 * Filters the part of the SQL query that performs the search.
		 *
		 * @since Unknown
		 *
		 * @param string             $sql           The SQL part that performs the search.
		 * @param LLMS_Student_Query $student_query Instance of LLMS_Student_Query.
		 */
		return apply_filters( 'llms_student_query_search', $sql, $this );

	}