Approaches the enemy king via the right square, not head-on.
With locked pawns White wants to get the king to c6 or e6 and win the d6 pawn. The black king on c7 tries to guard both entry squares. Walking straight at the enemy king is not always best.
Kb5 looks natural, but Black answers Kb7 and it is a draw. Find the only winning move.
Masters solve such positions with corresponding squares: for each square of the white king there is an answering square for the black king. The side that cannot reach its answering square loses.