According to the provided information, it seems that you have RadListView in DetailsView. In this view, RadListView provides a grid-like interface and displays columns. In order to get values from cells, you should access the column values for an item by using the their indexers. They can be either the index of the column, the name of the column, or the column reference itself. You might find the following help article useful on this topic: https://docs.telerik.com/devtools/winforms/controls/listview/populating-with-data/unbound-mode#adding-columns.
Here is an example of how to get sub items by using columns indexes:
Dim subItem1 = Me.radListView1.Items(5)(0)
Dim subItem2 = Me.radListView1.Items(5)(1)
Note, that the SubItems collection is intended for adding items at design time and it is not recommended to be used in runtime.
I hope this helps. Should you have any other questions, I will be glad to help.
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