related.php

<?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-structure/
 * @author      WooThemes
 * @package     WooCommerce/Templates
 * @version     3.0.0
 */

if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

if ( $related_products ) : ?>

    <section class="related products">

        <h2><?php esc_html_e( 'Related products', 'woocommerce' ); ?></h2>

        <?php woocommerce_product_loop_start(); ?>

            <?php foreach ( $related_products as $related_product ) : ?>

                <?php

                    $post = 40;

                    $post_object = get_post( $related_product->get_id() );

                    setup_postdata( $GLOBALS['post'] =& $post_object );

                    wc_get_template_part( 'content', 'product' );

                    wp_get_post_terms('$post_object');

                    ?>



            <?php endforeach; ?>

            <?php

                    $loop = new WP_Query( array(
                        'post_type' => 'product',
                        'post_status' => 'publish',
                        'posts_per_page' => 12,
                        'category' => $post,
                        'tax_query' => array( array(
                            'taxonomy'         => 'product_cat',
                            'field'            => 'slug', // Or 'term_id' or 'name'
                            'terms'            => get_query_var( 'product_cat' ), // A slug term
                            // 'include_children' => false // or true (optional)
                        )),
                        'orderby' => 'rand'
                    ) );

                    ?>

        <?php woocommerce_product_loop_end(); ?>

    </section>

<?php endif;

wp_reset_postdata();