Woocommerce 3+ posts related to product - Related posts in product page

content_single_product.php

// Custom WP query to get posts by current product category slug

$args = array(
	'post_type' => 'post',
	'tax_query' => array(
		array(
			'taxonomy' => 'category',
			'field'    => 'slug',
			'terms'    => $cats[0],
			'posts_per_page'      => 4,
		),
	),
);

$query = new WP_Query( $args );