CRM UI: restrict Installed Base component search

Hello!

We would like to allow key users to create messages via CRM UI (tcode SM_CRM, business role: SOLMANREQU).

We use SOLMAN 7.1 SP5.

When the key user tries to create a message via CRM UI, he/she can search for all Installed Base components.

Question

How can we restrict certain key users to search only for their own Installed Base components?