I've changed your worksheet_change sub from as follows:

Private Sub Worksheet_Change(ByVal Target As Range)
Dim i As Integer
    If Not Intersect(Target, Range("d10:d11")) Is Nothing Then
        For i = 1 To 2
            [d14:f14].AutoFilter i, Criteria1:="*" & Range("d" & i + 9) & "*"
        Next i
    End If
End Sub