how can hide a menu for one group specific user?

i like to hide a menu for one group specifity, but when i apply delete this remove all menu for all users, but i want to hide for one groups. explain: i inherit a groups to user from warehouse, but this specifity users i dont want to show menu stock out. for example i create a new groups users. i define in MY_module_folder/security/my_security.xml Almacen_mosel Encargado but i want to hide a menu stock out (this code put inside the my_security.xml). `` but this is dont work.