The usual scan of knight moves reveals that White’s most advanced knight has a fork at d7, but d7 is guarded by the Black bishop at e6. The bishop can’t be captured; you have no piece trained on it. But the bishop also guards the pawn at d5—which can be taken by your other knight at c3. So Nxd5, and you gain a pawn. If Black recaptures with BxN, you have Nd7+; after you next play NxQ and Black recaptures, you've won a queen and a pawn for two knights.

That's a simple analysis of the position along the lines we have been discussing. But there also is another, better way to size it up. Let’s look a little more deeply at White’s initial move Nxd5. To see its full significance we need to consider Black’s king and the constraints on its movement. White can give check with Qh8. This would be mate except that Black’s king has a flight square in e7. The e7 square itself thus is a vulnerability, or target, in Black’s position; and now return to White’s Nxd5 and see that it forks the e7 square and Black’s queen. So Black has to reply BxN to avoid mate, which in turn allows White’s next fork: Nd7+.

Indeed, White can turn these insights around and play an even stronger sequence by starting with Nd7+. If Black then plays BxN, White replies Nxd5 and Black has headaches: he is required to take emergency steps to prevent White from mating on h8, and finds that he has no way to capture White’s troublesome knight. He has to play g7-g6 so that his own queen has an open line to guard h8 if White’s queen lands there. But now White has NxQ, and (assuming Black moves his king to e7) NxR. Black is better off replying to the initial Nd7+ by moving his king to e7 and letting his queen be traded away for a knight. All this suits White, who still ends up winning Black's queen but at lower cost than in our original plan.

How would you see these richer ideas in the position? It all starts by focusing on the enemy king, how you threaten it, and how your threats are being staved off. We will see many times how this approach to analysis pays off with useful tactical ideas.