To get discount details of discount product only

Retrieve discount details specifically for discounted products.

add_action('woocommerce_get_price_html', function($html, $product) {
    $discount_details = apply_filters('advanced_woo_discount_rules_get_product_discount_details', false, $product); // it's product object for 3rd parameters
    if ($discount_details !== false) {
        print_r($discount_details); // If product has discount get the discount details  
    }
    return $html;
}, 10, 2);