Private Sub btnfiltrar_Click()
On Error GoTo Errores

If Me.txtfiltro.Value = "" Or Me.txtfiltro.Value = " " Then
    Me.ltbdatos.Clear
    Else
    Me.ltbdatos.Clear
    j = 1
    Set BD = ThisWorkbook.Sheets("APU")
    Filas = BD.Range("C2").CurrentRegion.Rows.Count
    For i = 2 To Filas
        If LCase(BD.Cells(i, j).Offset(0, 2).Value) Like "*" & LCase(Me.txtfiltro.Value) & "*" Then
            Me.ltbdatos.AddItem BD.Cells(i, j)
            Me.ltbdatos.List(Me.ltbdatos.ListCount - 1, 1) = BD.Cells(i, j).Offset(0, 2)
            Me.ltbdatos.List(Me.ltbdatos.ListCount - 1, 2) = BD.Cells(i, j).Offset(0, 15)
        Else
        End If
    Next i
End If

Exit Sub
Errores:
MsgBox "No existe.", vbExclamation
End Sub