See Beyond

• WWizards of the Coast2010-06-15
  Official Ruling
  You have to shuffle a card from your hand into your library even if you don’t draw any cards (due to replacement effects or Maralen of the Mornsong’s ability, for example). If your hand is empty, you don’t shuffle your library.
• WWizards of the Coast2010-06-15
  Official Ruling
  The card you shuffle into your library may be any card from your hand. It doesn’t have to be one of the cards you drew with the spell.

Rulings via Scryfall