What should I say to the old man in the warehouse district

Hint 1 of 5:

Have you been to Chen Lu's apartment?

Hint 2 of 5:

Until you have, there's nothing to say.

Hint 3 of 5:

Have you opened Chen Lu's safe?

Hint 4 of 5:

Then I guess you got the old scroll.

Hint 5 of 5:

Show him the scroll and listen to what follows.