Can you use Computer Search and fail to find a card in your deck?

No, you cannot. When searching for a Pokemon, Trainer, or other particular type of card you can voluntarily fail the search because the contents of the deck are unknown; but when searching for "a card" of any kind the game can tell whether there are cards in the deck and you must take one if instructed to do so. Although the contents of the deck are unknown, the quantity of cards in the deck is known.

Relevant cards