Check your RapportDB due to determine if all of your clients had registered with WDM. WDM should return more than 5 devices (if more than 5 devices are registered). Look at the dbo.client table to see the number of clients that are registered. If clients are missing, check the Wyse Device Agent (HAgent) application on the clients to verify that they are registered with your WDM server.
WDM Web Application (5.7.1 - 5.7.3)
By default, WDM Web application will display up to 30 devices/packages/images per page in any view on WDM Web Application. I do not believe that this can be changed.
WDM MCC Snap-in / GUI Management (5.7.0 and earlier)