material name not updating from customer material info record

Hi

I created a Customer-Material info record with VD51.There I put a nickname say, TT for a test material called Test1. I saved the record.

Now when I go to create a sales inquiry document with VA11,there in the Description of material i put TT and some Order quantity & I press 'Enter'.But the name of material doesn't automatically updates to Test1!!

Why is that?

Then what is the use of creating with cust. info record???