Just for the sake of example,Index says "Look at the top five cards of your library, put them back in any order." Does looking at the top cards of your library count as drawing, specifically for effects like Jace's Erasure?
Nope
Thanks
{index}
Rules for you
120.5. (http://imtgapp.com/forum/index.php?action=imtg;area=rule;number=120.5.): If an effect moves cards from a player's library to that player's hand without using the word "draw," the player has not drawn those cards. This makes a difference for abilities that trigger on drawing cards and effects that replace card draws, as well as if the player's library is empty.
Typically it doesn't say draw, so you did not draw.