The phrase "good liar" means someone who is skilled at deceiving or tricking others by telling lies that are believable and convincing. Full definition
It turns out Lance Armstrong is not only a really good at two - wheeled locomotion; he is a disturbingly good liar as well. (relevantmagazine.com)
Since authoritarian parents are often strict, their children may grow to become good liars in an effort to avoid punishment. (verywellfamily.com)
All our friends, who never even spent a thought on Indian food in their lives, got to know the food in my house and unless they are all really good liars (which I don't think they are), they all loved the curries and the dhals and the samosas they had in my house. (whereismyspoon.co)