to be able to set more than one value bound to a drop down list you must enable an option within your form.
With your form open within LiveCycle Designer, open the Options in Tools.
Click on Data Binding tab and make sure to have the Show Dynamic Properties option checked!
This will allow you to have multiple records in one Drop Down list from a database.
After this you can click on the Drop Down List and if you'd notice, in the Object Field Palette, you have the list of items you can have and the label List Items appear in green
Click on List Items and then you can specify which record you want it to display
Hope this help!