I know it's been a while since you posted, but I just joined recently. I'm assuming you mean by closing stock, closing inventory. If you want your opening and closing inventory figures to show on your P&L you will have to do this with a manual journal entry at year-end. There is no mechanism in QBO or QBDT to do this automatically. This is because the cost of goods sold is calculated at the time the sale happens and is removed from inventory then. If you want to create the opening inventory, plus purchases, less closing inventory on your p&l, you have to shift your cogs account around manually at year-end to show the presentation you like.
I hope that helps!