The original meaning of a famous saying is: "What I said is true, but I don't need to tell you everything I know."
I remember seeing this sentence in the video of Li Zhaoxing's speech at the earliest. He said that when he was a foreign minister, he asked Mr. Ji Xianlin of Peking University what he should pay attention to when he became a minister in the future. Ji Lao said: "No matter what you do, you must remember that you can't tell lies, but you can't tell all the truth."