[otrs] Hide Customers From Agent

Hello, I´ve looking through the documentation and google/mailing list to see if I could find some function to hide the customer list from the Phone Ticket view of an Agent (user), what I want is to have certain agents only be able to open tickets for a given customer and not be able to see the listing of all customers like I´m experiencing right now, I understand that based on the example of usage given by the documentation on the first pages, otrs seems not to be designed to do this (I´m talking about Max who is a fabricant who produces video recorders :) But maybe there´s some hiden configuration to do it, well if anyone knows how to do it it would be appreciated. Best Regars from Uruguay.