Change Woocommerce Related Products Display Category?

Question

WordPress

Hey! Tell me where to dig or in what direction to think, or maybe even how to do it?))
I have "related products" (related products) on the product page below. It just doesn't show up there at all. If I understood correctly, the products of the entire category are displayed there (and in this category there are more than 900 products of different subcategories). Therefore, I need the Related products block to display products of the third level subcategory that correspond to the product being viewed.
For example, the Product is located in a subcategory (dvr-ford-focus3). When viewing this product, similar products from the DVR category are now displayed below. And I need similar products to be displayed already from the "-focus3" subcategory.
I found only this code, which seems to be responsible for the output "

<?php
/**
* Related Products
*
* This template can be overridden by copying it to yourtheme/woocommerce/single-product/related.php.
*
* HOWEVER, on occasion WooCommerce will need to update template files and you
* (the theme developer) will need to copy the new files to your theme to
* maintain compatibility. We try to do this as little as possible, but it does
* happen. When this occurs the version of the template file will be bumped and
* the readme will list any important changes.
*
* see https://docs.woocommerce.com/document/template-struct..
* author WooThemes
* @package WooCommerce/Templates
* @version 1.6.4
*/
if ( ! defined( 'ABSPATH' ) ) {
exit;
}
global $product, $woocommerce_loop;
if ( empty( $product ) || ! $product->exists() ) {
return;
}
if ( ! $related = $product->get_related( $posts_per_page ) ) {
return;
}
$args = apply_filters( 'woocommerce_related_products_args', array(
'post_type' => 'product',
'ignore_sticky_posts' => 1,
'no_found_rows' => 1,
'posts_per_page' => $posts_per_page,
'orderby' => $orderby ,
'post__in' => $related,
'
$products = new WP_Query( $args );
$woocommerce_loop['name'] = 'related';
$woocommerce_loop['columns'] = apply_filters( 'woocommerce_related_products_columns', $columns );
if ( $products->have_posts() ) : ?>
<?php _e( 'Related Products', 'woocommerce' ); ?>
<?php woocommerce_product_loop_start(); ?>
<?php while ( $products->have_posts() ) : $products->the_post(); ?>
<?php wc_get_template_part( 'content', 'product' ); ?>
<?php endwhile; // end of the loop. ?>
<?php woocommerce_product_loop_end(); ?>
<?php endif;
wp_reset_postdata();

I tried the solution from this site: opttour(dot)ru/web/wordpress/pravilnyie-pohozhie-tovaryi-v-woocommerce/
Something obviously changed in the output, but did not solve the problem...