question do you have anonymous access running on the site?
what you need to do first is break inheritence of the doc lib from the site:
open the doc lib, hit settings, document library settings, actions, edit permissions, now you will see that you can select groups and users and set the permissions for each. what i would do here is take out any group or user that you dont want to see the doc lib in there. you have to keep in mind that if you have a member group or a viewer group that has all users that
will overide any person your trying to block. so in here you can add the member group you were talking about and give them the level of permission they need
now under settings still in the doc lib select anonymous access and make sure nothing is checked in there.
that is it.
let me know if you have any additional questions with this
