scent blood

Từ điển tiếng Anh - Cambridge Advanced Learners Dictionary

scent blood idiom
to believe that someone you are competing against is having difficulties and to use this to get an advantage for yourself
• The manager has already made some serious errors of judgment and it is clear that other employees scent blood.
Thesaurus⁺: ↑Advantage and disadvantage
Main entry: scent_idiom