How so?
Not quite sure what this question means. You can’t filter a slice via the user’s current context, so your initial approach at the start of this thread just can’t be done like that. Not to mention that it’s a nonsense formula.
Another option to try. You already have the slice for unique [cognome nome] values. Create a second slice for unique combinations of [cognome nome] and [schede] together, with:
[_THISROW] = MAXROW( table , rownumber , AND( [cognome]=thisrow.cognome , [schede]=thisrow.schede))
Then set up your target view on that 2nd slice and use a much simpler LINKTOFILTEREDVIEW action that just matches the [cognome nome].