That data is not available via the client. You could use a sql query like this to get CaseId or SearchID
Select CaseId, Name from tblCase
or
Select CaseId, SearchID, Name from tblIntSearches
and then run
SELECT Count(*) as NumOfItems, SUM(Size)TotalSize
FROM tblIntDiscoveredItems
WHERE CASEID = 5
SELECT Count(*) as NumOfItems, SUM(Size)TotalSize
FROM tblIntDiscoveredItems
WHERE SearchID = 13