For two-mana, you get to bring back a legendary creature from your graveyard to the battlefield, giving it haste for the turn
Like most Magic: The Gathering cards, the value of Search for Tomorrow depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Dominaria United Commander)
In Commander, where a valuable land is just a one-of in a hundred-card library, this can find you that Volrath's Stronghold, Academy Ruins, Strip Mine, or Maze of Ith that you need badly
Then the Punishment half is a Golgari X-costed sorcery that sweeps everything with that X cost of the artifact, enchantment and creature variety
This is good because an 8 mana commander is kind of steep