Fun question! There's an abundance in Vietnamese. Usually used by parents and/or old folk (I can hear it now...)

Mèo khen mèo dài đuôi — Literal translation "cat praises cat's long tail." A way of expressing narcissism.

Uống nước nhớ nguồn — Literal translation is "drink water, remember roots." So you'd pause, reflect, and remember where you came from.

Gieo gió gặt bão— Literal translation is "sow winds, weather storms." A way of saying "you reap what you sow."

Có công mài sắt có ngày nên kim — Literal translation "Perseverance grinds iron some day into needles." Used like "practice makes perfect."

Trời có mắt — Literal translation "Heaven has eyes." Usually used when someone's wronged, but don't worry - heaven is watching.

Gần mực thì đen, gần đèn thì sáng — Literal translation "near the ink it blackens, near the lamp it lights." You're influenced by those you're around.

Nuôi ong tay áo — Literal translation "raise bees in shirtsleeve." As in "to nurture a snake in one's bosom," kindness will be met by betrayal.