Hi Divash,
Most probably, these objects are not window objects and just drawn on the UIWnd window's canvas. You can try using one of the following features to get access to these objects: MSAA, UI Automation and Text Recognition.
To do this, please double-click the project node in the 'Project Explorer' panel, switch to the 'Properties' page and then select the corresponding option group under the 'Open Applications' section in the project editor. Add the 'UIWnd' item to the list of accepted windows and then check whether TestComplete can see individual objects within the 'UIWnd' window after this.
If this does not help, please post here an image of the 'UIWnd' window so I can see what kind of objects you want to work with.