Okay, your problem is basically due to color. The painting is very cold, lots of cool colors with the only warm color being the caboose(?).
So I did a quick Photoshop alteration. Add yellow to the bridge, add brown to the train and the smoke (I only added some brown to the train in this alteration). Reduce the vibrancy of the blue in the sky. Add either blue or green to the shadows in the rocks (I didn't do this, it would have taken too much time). Add some warm colors to the greenery (I didn't do that either), yellow/red flowers or dead grass, something like that. Darken some of the shadows in the closer rocks.
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