Search AD Computer for hostname and description

In this example EMEA devices with Latitude e7470 in the description field:

$Properties = @('Name', 'Description')

Get-ADComputer -Filter {Name -like "*EMEA" -and Description -like "Latitude e7470"} -Properties $Properties | Select $Properties

To get a count of objects found (after you created the $properties variable above):

(Get-ADComputer -Filter {Name -like "*EMEA" -and Description -like "Latitude e7470"} -Properties $Properties | Select $Properties).Count