BUG: Multiple products with customizations = multiple fields in backend order

[teleservicecenter]

We have a store with multiple electronics products. We use the customization field to enter the unique serialnumber of the product so we can later display it on the customers invoice. (He needs it for waranty).

But when I search for a product in the backoffice (order creation page) and multiple results show, also multiple customization options show. In the example (see pic) I searched for "Samsung Galaxy" and got a result of about 80 products, with a matching number of customization fields.

Any ideas as to how I can fix this?