To record invoice payments, read here (link).

When recording a payment for confirmed invoices, within the Payment Editor window,

  1. Check the "Deduct withholding tax" to display withholding tax fields.
  2. Select a withholding tax type.
  3. An automatic withheld tax amount will be display in the adjacent Amount field. Custom the amount when needed.

If you cannot find a applicable withholding tax type, you can manage the tax list (link).

After recorded, the withheld tax amounts will be displayed in the payment table for your reference.