How to retrieve "similar" type

Hi,
i would really appreciate help with the following, something like upsell for uberkart, but without using uberkart.

Via Views and exposed filter "TYPE" user can change one type and get the corresponding product.

Every product has a field "grouping #". So my products grouping #s are numbered 1, 2, 3. Let's say group 1 is mouse, keyboard, 2 is monitor, tv, etc.

Now, I need the user to filter out TYPE "Mouse", show him the type but also including "corresponding products".

The view should be something like this :

User chooses Mouse:

and he gets:
Mouse
Keyboard.

User chooses Keyboard:

and ghe gets
Mouse
Keyboard.

Right now, if i chose "Mouse", i get only "mouse".

simply, i don't know how to order droupal to show:

for selected, take selected.grouping# and show every product that corresponds with it.

Thanks so much!

Michal