WooCommerce - Related products pool size

<?php
  // fetch related products from a bigger pool
  // code goes in functions.php for your child theme
  add_filter('woocommerce_related_products_args', 'my_related');
  function my_related($args) {
    global $product;
    $pool_size = 10;
    $related = $product->get_related($pool_size);
    if ( sizeof( $related ) == 0 ) return $args;
    $args["post__in"] = $related;
    return $args;
  } // end function