I'm guessing that what you have is a join on two entirely unrelated values: item ids and my_order ids. What is "MyOrders.ID"? You say that MyOrders has OrderID (matching Order.ID), ItemID (matching MyItems.ID) and order value. Thus, if I understand you, there is nothing called MyOrders.ID. While you can have it (to uniquely identify an item belonging to a specific order), it's also completely unnecessary, since that is allready uniquely identified by the pair (OrderID, ItemID).
A right join is the same as saying right outer join, which means that you take all items, wether they belong to an order or not.
Thus, you should have a left join (from myorders to myitems), and since I doubt you'd have empty orders, i.e. orders without items, there will be no difference between a left inner and a left outer join. But if there are empty orders, then a left join would include those, while an inner join would not.
So, what you want is MyOrders INNER JOIN MyItems ON MyOrders.ItemID = MyItems.ID
But I would also personally rename MyOrders, since that seems to imply that is is an entity for an order, while it's actually an entity for an ordered item. That is, the three tables are order, item and ordered_item. The order table contains information about the user who made the order (user_id), order_date, shipping_adress, billing_adress etc. The item table contains the items that can be ordered, their current prices etc (unless that is in another separate table). The ordered_item table is the one containing order.id, item.id, units, price/unit, or in other words: it contain the contents of the order.
