Here is a simple PowerShell script example on how to export Domain Users to a .csv file for specific attributes:
samAccountName
Display name
First Name
Last Name
Description
Connect-QADService -proxy
$users = (Get-QADUser -DontUseDefaultIncludedProperties -IncludedProperties samAccountName,displayname,givenname,sn,description)
$users | select samAccountName,displayname,givenname,sn,description | export-csv c:\MyExport.csv -NoTypeInformation