在（某人的）知识范围之外
not in your area of knowledge
Financial matters are beyond my ken, I'm afraid. 金融方面的事我恐怕不懂。
She was convinced that there are supernatural happenings beyond our ken.
These technological systems are beyond the ken of most of us.
Some of the questions were a bit beyond his ken.
Their works spoke of physical and psychological laws that were beyond their ken.
See also: ken noun