Trump should call each of the 10 highest ranking CIA people in, one by one, one at a time, and ask them for a list of the people who are leaking.
If they do not produce the list, he should say: “Either you do not know what is going on in your agency and are therefore incompetent or you are part of the leaking and cover up.”
“I can not have either in my administration. You are fired.”
Before he got to the end of the top 10 managers, he would get the names of the leakers.
There’s actually a simpler approach than that. The CIA counterintelligence office - the “mole hunters” - is the most universally-feared office in the CIA. Have Mike Pompeo bring the Associate Deputy Director of Operations for Counterintelligence in and pose the question to him.
Here’s the reason why they are so feared:
Paul Redmond - the guy who wrote this - was mentored by James “Jesus” Angleton, who was probably the most successful, most ruthless and most feared mole hunter in the history of intelligence, thus the nickname “Jesus”.