You probably need something like the following, but if there are lots of these values as seems to be the case you would be better putting the codes and their values in an Excel worksheet and reading them from the worksheet.
Code:
Private Sub CommandButton2_Click()
Dim sVia As String
Dim lPK As String
sVia = ComboVia.Text
lPK = textPK.Value
Select Case sVia
Case Is = "A-68"
If lPK > 81 And lPK < 85 Then
Rellenar "termino", "Castejon"
Rellenar "partido", "Tudela"
End If
If lPK > 84 And lPK < 99 Then
Rellenar "termino", "Corella"
Rellenar "partido", "Estella"
End If
If lPK > 98 And lPK < 113 Then
Rellenar "termino", "Fontellas"
Rellenar "partido", "Tafalla"
End If
Case Is = "NA-3010"
If lPK > 20 And lPK < 25 Then
Rellenar "termino", "Cortes"
Rellenar "partido", "Tudela"
End If
If lPK > 24 And lPK < 35 Then
Rellenar "termino", "Ribaforada"
Rellenar "partido", "Tafalla"
End If
If lPK > 34 And lPK < 44 Then
Rellenar "termino", "Novillas"
Rellenar "partido", "Estella"
End If
End Select
lbl_Exit:
Exit Sub
End Sub