be a closed book

To be difficult to know or understand. She's such a private person that I don't know much about her. I guess she's a closed book. I'm a scientist, so art will always be a closed book to me.

be a closed book

to be something that you know or understand nothing about (usually + to ) I'm afraid physics will always be a closed book to me.

Common Names:

Name	Pronounced	Usage
Taner	-	Turkish
Lykos	-	Greek Mythology, Ancient Greek
Cato (2)	-	Dutch
Ansehelm	-	Ancient Germanic
Verner	-	Swedish, Norwegian, Danish
Asa	['eizə]