小题大做

小題大做
xiǎotídàzuò
to make a big fuss over a minor issue (idiom)

CEDICT

alternative form of 小題大作 /小题大作 (xiǎotídàzuò, “to make a fuss over a trifling matter; to make a mountain out of a molehill; to blow out of proportion”)

Wiktionary

科举时代的习惯用语。凡是考试题目从四书中出来的，称为「小题」；从五经出来的，称为「大题」。用五经文的文章章法来做四书命题的题目，就称为「小题大做」。后用以比喻人将小事视为大事办理，有故意夸张的意思。

重編國語辭典

Entry Composition

1 小 xiǎo
  1. small
  2. tiny
  3. few
  4. young
2 题 tí
  1. topic
  2. problem for discussion
  3. exam question
  4. subject
  5. to inscribe
  6. to mention

classifiers: 個, 道
3 大 dà
  1. big; large; great
  2. older (than another person)
  3. eldest (as in 大姐 dàjiě)
  4. greatly; freely; fully
  5. (dialect) father
  6. (dialect) uncle (father's brother)
4 做 zuò
  1. to make; to produce
  2. to write; to compose
  3. to do; to engage in; to hold (a party etc)
  4. (of a person) to be (an intermediary, a good student etc); to become (husband and wife, friends etc)
  5. (of a thing) to serve as; to be used for
  6. to assume (an air or manner)