a thing or two

Definition

› some matters, facts, or information: I'm having trouble paying attention - I have a thing or two on my mind. Why don't you ask Andrew about it? He knows a thing or two about (= has some knowledge of) computers. She thinks she knows everything about raising children, but I could tell her a thing or two (= some information she does not know).Information and messages

(Definition of a thing or two from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)