Changes after PR released

Hi, I am quite new to MM. I appreciate dearly if someone can help me here.

When we set PR release indicator changeability to 4 (Changeable, new release in case of new strat. or val. change), once PR is released, if there is any changes to qty or value, the PR will need to be released again.

How can i set it to, any changes in the PR (besides qty or value) also require new release? For example changing the material, plant or short text.

I tried to create new field selection key, but i am not sure how to configure it.