What should I do in the Library?

Hint 1 of 5:

There are a few pages to read and some eavesdropping to do.

Hint 2 of 5:

You need the key from the table, so take it.

Hint 3 of 5:

Listen in on a important conversation between Lurka and Tobias through a
special tube.

Hint 4 of 5:

Use a spy device behind a red curtain.

Hint 5 of 5:

Adjust the overhead mirrors to see 3 different scenes that will mean more to
you shortly.