在函数上添加以下代码。主题目录中的php文件。

<?php
    function __search_by_title_only( $search, &$wp_query )
    {
        global $wpdb;
        if ( empty( $search ) )
            return $search; // skip processing - no search term in query
        $q = $wp_query->query_vars;
        $n = ! empty( $q[\'exact\'] ) ? \'\' : \'%\';
        $search =
        $searchand = \'\';
        foreach ( (array) $q[\'search_terms\'] as $term ) {
            $term = esc_sql( like_escape( $term ) );
            $search .= "{$searchand}($wpdb->posts.post_title LIKE \'{$n}{$term}{$n}\')";
            $searchand = \' AND \';
         }
         if ( ! empty( $search ) ) {
             $search = " AND ({$search}) ";
             if ( ! is_user_logged_in() )
                 $search .= " AND ($wpdb->posts.post_password = \'\') ";
              }
          return $search;
      }
    add_filter( \'posts_search\', \'__search_by_title_only\', 500, 2 );
?>