Access DB: FindRecord Method

I have used DoCmd.FindRecord to search for an ID #. When used, it searches all Fields. If I limit it to the Current Field, it finds nothing. Does anyone have tips. See Code Below:

Private Sub cmdSearch_Click()
On Error GoTo Err_cmdSearch_Click
DoCmd.OpenForm “Book Form”
txtNum.SetFocus

If Not txtNum.Value = “” Then
DoCmd.FindRecord txtNum.Value, acDown, , acSearchAll, True, acAll
txtNum.Value = “”
DoCmd.Close acForm, “ID # Search”