It doesnt take that much thought to realize what determines bringing your non showdown winnings up.

1. Play more in position, less out of position.
2. Engaging less preflop in spots where you cant win with bluffs (Calling multiway with sc's from the sb, calling hands like AJ to UTG raises).
3. Balancing bluffs in nearly every spot where you have the necessary amount of FE.
4. Being able to pot control your weaker hands. Making correct folds on earlier streets.
5. Not making bluffs without equity.

Essentially, having higher non showdown winnings takes all the skill set you need to become a good player. That being said, even though super high non showdown winning graphs are pretty sweet looking, they dont necessarily mean the person is playing that well. There are a lot of spots where you are going to want to play hands for pure sd value and implied odds + pot odds. You'll probably note the high non showdown winning guys are putting any 8 out draw or better in on the flop or turn no matter what, even though there is no FE. There's also spots where it may be optimal to call 4bets rather than shove over them, yet that will yield a lower non sd winnings. 4bet folding sometimes rather than 4bet calling everything will also yield lower non showdown winnings.

Pretty much your likely doing fine if your non sd winnings are around even. But if your bleeding money look at some of the aspects of the game I wrote above. There's almost no way your playing in a game that would make bleeding a lot in non sd pots optimal.