Rule 701.17c

If a player is instructed to search a hidden zone for cards that match an undefined quality, that player may still search that zone but can’t find any cards. Example: Lobotomy says “Target player reveals his or her hand, then you choose a card other than a basic land card from it. Search that player’s graveyard, hand, and library for all cards with the same name as the chosen card and exile them. Then that player shuffles his or her library.” If the target player has no cards in his or her hand when Lobotomy resolves, the player who cast Lobotomy searches the specified zones but doesn’t exile any cards.

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