I am hoping you will be able to look at my edit and understand why it is so important not to "just keep snapping." Whoever made the comment was referencing the rule of thirds because you did not compose or expose in such a manner as to present a single subject, but rather a scene comprised of a nice sky and some hillsides, some boats and fishermen in the water, a lagoon, and two boats shoved up against the left side of the frame.The lighting was right for every component in the scene but the most important one: the two boats.
One of my pet peeves in looking at a photo is to find there isn't any room for the primary subject to "look out" of the frame comfortably. In your shot, the bow of the fore boat is jammed right up to the frame, essentially strangling the shot. All the area behind the boats is pretty much superfluous in that it doesn't do anything to move the eye toward the boats.
You also have a bright area about midway across the face of the hills which pulls the eye away from the boats, and another bright shoreline/dock area which also pulls the eye away..
I added some space in front of the boats (expanded the canvas size, then cropped accordingly), using the clone tool to rebuild what I needed to fill the scene. Some gradient fills, and levels adjustment helped me to get the light on the boats and off the background.
Using the "Rule of Thrids as described by some of the others on here, look at the edit and see how by filling the frame, you are essentially creating this rule rather than trying to make the rule fit. This edit could even stand some more cropping off the top.