大多数必要的信息可以在Code Reference: WP_Query | Class . 其他有用资源Theme Handbook: Conditional Tags. 下面的代码包含一些明确的注释。请注意，这是未经测试的代码，因此不能保证，但它应该可以让您继续。

add_action( \'woocommerce_product_query\', \'custom_woocommerce_product_query\' );
function custom_woocommerce_product_query( $q ) {
  if ( ! is_admin() ) {   
    //query for the out of stock items we want to exclude
    $oos_query = new WP_Query( [ 
      // items must be older than 1 month
      \'date_query\' => [ [ 
        \'column\' => \'post_date\', 
        \'before\' => \'1 month ago\' 
      ], ],
      //only out of stock items...
      \'meta_query\' => [ [ 
        \'key\' => \'_stock_status\',
        \'value\' => \'outofstock\',
        \'compare\' => \'=\',
       ], ],
      //we want products, nothing else
      \'post_type\' => \'product\',
      //we want them all
      \'posts_per_page\' => -1,
      //the ids are enough, no need to get more data 
      \'fields\' => \'ids\',
    ] );
    //getting array of ids from object
    $exclude_ids = $oos_query->posts;

    //excluding the above queried products from woocommerce\'s product query
    $q->set( \'post__not_in\', $exclude_ids );
  }
}