切中要害

1. • to hit the target and do real damage (idiom)
2. • fig. to hit where it hurts
3. • fig. to hit home
4. • an argument that hits the nail on the head

Character by character

• 切(qiè)definitely
• 中(zhòng)hit a target
• 要(yào)want
• 害(hài)do harm to