翻小腸子

Simplified: 翻小肠子

fānxiǎochángzi ㄈㄢ ㄒㄧㄠˇ ㄔㄤˊ ˙ㄗ

    • to go on about trivial old matters

Character by character

Saying俗语俗語

Idiom惯用语 · Rarely used now

Literally
to turn over one's small intestines
Meaning
To go on about trivial old matters to someone. Mildly critical.

Sources