• Several people writing at once means duplicates, gaps and typos. At the wedding reception, three or four relatives open envelopes together. One guest gets entered twice, one envelope never gets entered, one amount gets an extra zero.
• Nobody knows who changed what. A cell is overwritten, a row disappears. By the time you reconcile, there’s no trail left to follow.
• Notebooks get lost, and every occasion starts from scratch. Come the next birthday, housewarming or memorial, you rebuild the list again and can’t check who came or what they gave.
• Shared plans drown in group chats. Who’s booking the car, who’s ordering the food, who still owes the group fund: all buried in hundreds of messages.

Sổ Mừng Cưới (“the wedding gift book”) was built for exactly this: one shared book for the whole family that is quick to fill in, keeps a trail, doesn’t get lost — and never touches your money.