To display the product details for a line item simply click on the Display Product Details button at the top of the Maintain Order Line Item Screen.

Once you click on the Display Product Details, a window will pop up showing the line item details of this product:

When you do open up the product details, use caution to not show this screen to the customer because it does show the product cost of the line item. This window will show you the line item in more detail to ensure you have the correct line item.