Question

does this sentence making any sense?
the book, which is about a murder on the Nile, which was written by Agatha Christie.

Answer 1

Answer:

The proper way to say that is:

"The book, which is about a murder on the Nile, was written by Agatha Christie."

Explanation:

you added an extra "which" in there and it was unnecessary

Answer 2

Or you could write: The book written by Agatha Christie, is about a murder on the Nile.