<?php
<!-- In order to match the testmimonials involved later, first we need to store the ID of service/ product on the current page -->
<!-- get_the_ID concerns with this current page's ID -->
    $product_id = get_the_ID();
?>

<section class="product-testimonials">
<!-- Now, consider only the Custom Post Type named 'tu-testimonials' -->
			$args = array(
				'post_type' => 'tu-testimonials',
				'posts_per_page' => -1
			);
			$query = new WP_Query($args);

<!-- If 'tu-testimonials' contains any post -->
			if( $query -> have_posts()){
				?>
				<h3>Our Clients Say</h3>
				<div class="slider">
				<?php
				while ($query -> have_posts()){
					$query -> the_post();
          <!-- And if 'tu-testimonials' post type has any ACF field set up -->
					if(function_exists('get_field')){
            <!-- Then consider an ACF field named 'mentioned_services' -->
						$testimonials = get_field('mentioned_services');
            <!-- If this ACF field 'mentioned_services' contains any post -->
						if ( $testimonials ){
							foreach ($testimonials as $id){
								if( $product_id === $id ){
                  <!-- Then output the post content if this testimonial 'post id' equals to the 'product id' on this current product page -->
									the_content();
								}
							}
						}	
					}
				}
				?>
				</div>
        // Closing Testimonial Slider
				<?php
				wp_reset_postdata();
    }			
?>
</section>