GridMarket homepage products listing Please help

I am using MarketPress plugin and GridMarket theme. If you go to the homepage of my website http://ubidphones.com you will see that GridMarket theme show all products I have listed in the MarketPress plugin. Before using the GridMarket them I used a different them and on my homepage I was able to use shortcodes to display the products I wanted to show. I need to know where file to edit or is there a way that I can tell GridMarket to not show all products on the homepage, only show products that I have listed under a shortcode.