Late to the post but beside being able to search by VLAN in the UDT search field you can also make a report for it - here's a quick one I created that you can add a where vlanid = 'xxx' at the end to limit your response.
SELECT n.caption, up.portifdescr,up.portdescription,up.speed,case up.duplex when 0 then 'None' when 1 then 'Full' when 2 then 'Half' end,up.administrativestatus,up.operationalstatus,uv.vlanid
FROM UDT_Port up
inner join UDT_vlan uv
on up.portid = uv.portid
inner join nodes n
on up.nodeid = n.nodeid