Variants of a mold are catalogued separately, so each one has its own sets and minifigs. Check these too if something you expect is missing here.

• 646bc01 Window 1 x 6 x 2 with Shutters [Old Style Extended Lip & Glass] Alternate of this part
• 646b Window 1 x 6 x 2 with Shutters (old type) with Extended Lip, no Glass Mold of this part
• 646c Window 1 x 6 x 2 with Shutters, without Glass for Slotted Bricks Mold of this part