linhtran on "[Plugin: WooCommerce Products Per Page] GoodStore theme"

Hi,
I'm using GoodStore theme.Someone tell me why the plugin doesn't display on my shop? Maybe,it has some problems with:
1) 'loop_shop_per_page'
2) 'posts_per_page'

Thank you

https://wordpress.org/plugins/woocommerce-products-per-page/