I'm surprised that as of this writing, none of the reviews on this page have mentioned Lórien's Wealth yet, because that's the first card that I think of when I think of Gandalf's Search. As soon as I saw the two right next to each other in the (revised) core set, I wondered what the use of Gandalf's Search could be over Lórien's Wealth. It may be the only way in the core set to pay 1 resource to draw 1 card, but paying 2 or more resources to only draw 1 card makes this card lose to Gléowine and Lórien's Wealth, which are both also from the core set. And rearranging what's on top of the player's deck is not what you want to be paying for, because having cards in hand is much better than having them on top of the deck. As a matter of fact, for many of the game's first cycles, there were barely any cards or scenarios that cared about what was on top of your deck; and by the time those scenarios and cards started becoming more common, we had already gotten much better deck rearrangement options (Imladris Stargazer and Wizard Pipe to name a few). The only time I have ever used this card was when playing the mono- starter deck from the revised core set, and that was only to pay 1 resource to draw 1 card.
I did see a comment on a Youtube video a while ago (I don't remember which video) where the commenter had made a house rule alteration for Gandalf's Search: it costs 3 instead of X, and lets the chosen player search their entire deck for any card rather than the top few cards of their deck. Now that made me think. If that were how the card worked instead of what we got, I wonder how much more play would it have seen? Would it have been worth it to use a deck slot and pay 3 resources to choose any player to search out their combo piece? And, on the other hand, would it have been healthy for the game to have a deck-searching card right from the beginning? But I'm not a designer.