To search the Data Source via the LNC, the Data Source's module objects need to be downloaded to the Admin DB. From there, the LNC Admin may then set up the Search Settings and the Select Associations features.
In each user record, that user must have the LNC Enabled, and have the Associations section selected for Enable(Admin Config). Otherwise, the LNC Admin DB default configuration is used.
As with other updates made in the LNC Admin DB, the user will not see the changes until you run the Update All agent. This can be done using the button located at the top of the Admin DB view.