filter by colour (feature and attribute at the same time)

[Yves]

Hello,

Sometimes a product is yellow, sometimes it is optional yellow (or red, green, ...). They both exists and must be found in the search results together if I need a yellow product.
If I want to organize a search filter, I would like to create a search option by colour that will show all the products with that specific colour feature or attribute.
How can I do that without having to display the feature colour filter next to the attribute colour filter?

Thanks in advance!