Ranger build Cruel

Ok so i am kind of a noob when it comes to planning builds in ARPGs. As such i created a ranger that is now level 56 and is beeing played on cruel difficulty act 3. No i will link the tree in this post but basically i went for having big physical and bow damage and increased attack speed. for mana i use mana leech and also life leech for...well life. The problem now is that while i have good damage output (at least as far as i fell) the life leech for life is sometimes not enough especially for bosses that have big dps (they sometimes one shot me). I am already starting to notice that i am starting to die more easily and i know some big bosses are gonna be coming up soon. My question is what can i do to increase my survivability without sacrificing too much of the attach and speed stats(if possible of course). Link to tree:
http://www.pathofexile.com/passive-skill-tree/AAAABAIAAAHRBLEGIwiJFSAV8Bm0Gf4bARutI9MknSU_JyEs6S2DMHwylE4qUUdbr11oXkViWm8ndct7FH8CjX6Nv49gkvOVBZXImmqa8aEioaSiQKbgp9Sr0q_rsKu3tr6nwUnEosjcyqnNmNN-2cbajd0N35jh2-pi73r05vT49qP66_4J_h3-yA==

Why there are not a single health node in your tree???
Try the master to craft maximum life.
Add acrobatics and you r gud to go.