Extract
{U} Sorcery
Search target player's library for a card and exile it. Then that player shuffles his or her library.

Which option below, if any, are equivalent to the actual card text above?

An option: Name a card, and then look through opponent's library for it. Exile a copy if any are found in the library. Opponent shuffles the library afterwards.

Another: You may look through opponent's library; exile any card of your choice. Opponent shuffles library afterwards.

In short, do I need to know what I am looking for?