Dataset not returning data

Hi ,

local!datasubset: todatasubset(index(local!fulldatasubset.data,wherecontains(toString(local!name),touniformstring(local!fulldatasubset.data.testName)),null),local!gridSelection.pagingInfo),

When i try to print todatasubset(index(local!fulldatasubset.data,wherecontains(toString(local!name),touniformstring(local!fulldatasubset.data.testName)),null),local!gridSelection.pagingInfo) in one text field its printing data but i try to print with identifier its not returning anything.

todatasubset(index(local!fulldatasubset.data,wherecontains(toString(local!name),touniformstring(local!fulldatasubset.data.testName)),null),local!gridSelection.pagingInfo) - Returning data

count(local!datasubset.data) - returning count

local!datasubset.data No O/P

local!datasubset - No o/p

What could be the issue.