a question on probability from Sklansky Hold Em Poker

[Chefskeez6]

Page 107 Probability: Introduction 107

I am having a hard time understanding what this table means.
For instance - 9 wins (flush draw) 35.0%
- 15 wins (str flush draw) 54.1%
What does this mean, if i have two pocket cards of the same suit and i flop 2 more of the suit there is 9 more cards remaining of the same suit, are my odds of making the hand 35% and if they are how can my odds of making a straight flush be 54.1 % even if i am drawing for an open straight flush there is only two chances to get one of two cards out of a remaining 47 unseen cards. I am sorry if this is a stupid question but i could use a little help here. Thank You.