BindingSource.Find by operator LIKE

How to find a letter begins them string with operator LIKE and object BINDINGSOURCE
The following code does not work :

Dim sString As String

sString = "Like 'C*'"

Dim foundIndex As Integer = Me.DATI_BindingSource.Find("Cognome", sString)

If foundIndex > -1 Then

DATI_BindingSource.Position = foundIndex

Else

MessageBox.Show("Nessun nomimativo con questa lettera iniziale.", "GSL", MessageBoxButtons.OK, MessageBoxIcon.Information)

End If

Thanks and ........excuse my imperfect English language.