Chrissie beat me to it.
Dimensionality is usually from being lit from an angle.
When I've run workshops in the past, I've taken something and just photographed it from every angle with a single light. Straight on, 15, 25, 45, 60, 90° angles, totally backlit, etc. It really gives an idea of how light falls off something.
If too much light is spilling from the source, you can often fashion anything into a barn door to block it where you don't want it to go.
Your results look great so far. It's nice to see more shadowy compositions.