get_the_terms and get_term_by problems with showing categories and subcategories

Hello everyone,

The following code displays category linked to subcategories. The problem is that only one subcategory is shown despite several are available.

How can I modify this code so more subcategories($val) are shown on the page?

add_filter("woocommerce_product_tabs", "custom_tabs");
function custom_tabs( $_original )
{
	global $post;

	$aTerms = get_the_terms($post->ID, "product_cat");

	$aUse = array();
	foreach( $aTerms as $oTerm )
	{
		if( $oTerm->parent > 0 )
		{
			$oParent = $aTerms[$oTerm->parent];
			if( empty($oParent) )
			{
				$oParent = get_term_by("id", $oTerm->parent, "product_cat");
			}
			// Original line
			$aUse[$oParent->name] = $oTerm->name;
		}

	}

	echo "<div class='specifications'>";
	foreach( $aUse as $cat => $val )
	{
		?>
			<div class="spec-wrapper">
				<div class="type">
					<?php echo $cat; ?>:
				</div>
				<div class="value">
					<?php echo $val; ?>
				</div>
			</div>
		<?php
	}
	echo "</div>";

	return $_original;
}

This is the page:
https://www.legrandcru.nl/product/soave-classico-azienda-agricola-fornaro-2013/

Serveertip is a category and Vis gestoofd is a subcategory, but there are more subcategories but they don’t show up.

Alot of thanks in advance for your time, hope you can help me out.

Greetings,

Mickey