Add a card

To add a card to your hand is not the same as drawing a card. If "Protector of the Sanctuary" is on your side of the field, your opponent cannot use "Pot of Greed" to draw, but they can still use the effect of "Sangan" to add a card.

To draw a card is a form of adding a card from your deck to your hand. If "Blackwing - Breeze the Zephyr" was drawn by a card effect, then you can Special Summon it. Because of this, the card "Thunder King Rai-Oh" had to clearly make an exception in its lore; and the card "Droll & Lock Bird" further clarifies this situation.