woocommerce product query

<ul class="products">
    <?php
        global $post;
        // Setup your custom query
             $args = array('posts_per_page' => 4,'post_type' => 'product',
            //add category
            'tax_query' => array(
            'relation' => 'AND',
        array(
            'taxonomy' => 'product_cat',
            'field' => 'slug',
            'terms' => 'html' //example : ‘term’ => ‘red-shoes’, ‘books’, ‘fiction-books’.
        )
         ),
             'orderby' => 'title',
             );
        $myposts = get_posts( $args );
        foreach( $myposts as $post ) : setup_postdata($post); ?>


         <li class="col-sm-4">
         <div class="shop_product_inner">  <!-- shop_single here woocommerce img id you can ise usr won crop id  -->
                    <a href="<?php the_permalink() ?>">
                        <?php if ( has_post_thumbnail( get_the_ID() ) ) {
                             the_post_thumbnail('shop_single', array('class' => 'img-responsive project-image'));
                        } else {
                  echo '<img src="' . woocommerce_placeholder_img_src() . '" alt="Placeholder" />';
                        } ?>
                        <div class="shop_product_inner_caption">
                            <h2><?php the_title(); ?></h2>

                            <p><?php echo $product->get_price_html(); ?></p>
                            <?php woocommerce_template_loop_add_to_cart(); //ouptput the woocommerce loop add to cart button ?>
                        </div>
                    </a>
                </div>

        </li>

        <?php endforeach; ?>
    </ul>