灰吹きから蛇が出る（はいふきからじゃがでる）

Japanese vocabulary

Meaning: unexpected things can come from unexpected places; small things can lead to unexpectedly large consequences

See it used in real works

• Example sentences from Japanese novels & web fiction (Massif)
• Hear “灰吹きから蛇が出る” pronounced in real videos (YouGlish)