Some of the principles of art as represented in Van Gogh's "Olive Trees with Yellow Sky and Sun" are as follows:
Form. The scene represented appears three-dimensional, with the height coming from the placement of the sun in the sky and the shadows it casts. The depth of field comes from the proximity of the sun to the objects on the ground and those objects to each other. For example, the groves of trees in two lines diminishing towards the mountains in the background. Width is represented in normal-view perspective, with the painter/seer looking out over two rows of olive trees. It's likely the painter/seer would see additional trees in the periphery, but they are not included here.
Space. Space is included in the foreground of the trees which achieves a sense of approaching the grove, versus standing inside of it. The space between trees is orderly, representing agricultural planning rather than the random order we would expect in a nature setting. The space between the mountains and sun provides the canopy of sky for the canvas.
Harmony. According to his letters, Van Gogh chose the olive grove as a subject in order to observe the effects of light on the olive leaves, ground, mountains, and other shapes. Through the use of similar color palettes, it is possible to interpret times of day and seasons in the canvas. Some critics point to "Olive Trees with Yellow Sky and Sun" as a possible example of memory or fantasy, as the shadowing does not appear consistent with the time of year. However, there are many possible explanations related to weather and shadows we can't possibly know.