Why does everyone leave the meeting at the Harkers'?

Hint 1 of 12:

You need evidence that Dracula might still be alive.

Hint 2 of 12:

One of the characters in this game is really quite an expert on vampires.

Hint 3 of 12:

The bookstore owner probably has some information that can help you.

Hint 4 of 12:

But that information is hidden away -- he won't give it to you willingly.

Hint 5 of 12:

That means that you need to break in.

Hint 6 of 12:

Come at a time when he's not going to be there, like very late at night or
very early in the morning.

Hint 7 of 12:

And you're going to need a way into the bookstore.