How to hide child products from related product Search in Back end

[uberweb]

I have a shop with 8000 products and many of the products are child products. When i try and add related products and type in a SKU in the Search for Related Products in back-end Custom Fields the results show all the products both parent and all the child products. I see an Image and the product name. How can i do the following

1. Only show Parent product in this search results no child?
2. Or if this is not possible how can i add the SKU to appear in the image below the product name so this way i can see by sku? see my attachment.

Thanks in advance to anyone who know how to solve this

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