SSH pot equity question?

[PapiChulo503]

on page 36 it says ", you have flopped a nut flush draw against your opponents. You have a 35% chance to make your hand by the river, and therefore, also about a 35% pot equity."

If you have a nut flush draw you have 9 outs out of 47 unseen cards or 4.1 to 1 according to the table on page 30. Isnt that more like a 20% chance of making your hand by the river? Or am I not taking something into consideration?

The one thing I noticed was the use of the word MAKE. Does make mean MAKE the flush? or does MAKE mean winning the hand?