can't edit product per row things on shop page

I am using topshop theme at godigie.com/smenterprise. It was showing 4 products per row before. Now it is showing only two products per row on shop page. I tried out setting up show post limit attribute from Settings > Reading. Tried woocommerce docs intstructions snippets, also tried to use a couple of plugins that claims to do the same. no effect. please help.