Order with multiple items from multiple sellers

In our applicaiton it's possible to order items from multiple suppliers. The buyer can only see their own orders by xPath. I want to create the same for the suppliers. 

The suppliers can only see the orders where they are participating in, with 1 or more items. When they open the order they only can see the items that are ordered from them. Is there anyway to solve this in an easy way?

This is our domainmodel;

Thanks in advance.