IMO, The image you posted is not sharper than your sharpest images....it's an average example of sharpness not an exceptional one.

You'll need to show us additional images....pictures are worth many more words than explanations of those pictures

In my experience uber-sharpness is a combination of the factors;
1 - shutter speed. make sure it's appropriate for your subject and hold holding ability.
2 - post processing. You can easily sharpen one area and not other areas. Selective sharpening is part of the secret sauce. Oversharpening kills an image so make sure you don't go too far. There are also other pluggins and programs that can deftly add sharpness and 'microcontrast' and look superb when they are not overused.
3 - additional advanced techniques like focus stacking which is normally reserved only for landscapes.
4 - Focusing on elements with ACTUAL detail (eye lashes, grasses, the weave in a shirt) will also reveal that detail when in sharp focus. Things that naturally have fever details (like soft clouds) can never look razor sharp.
5 - Lighting - front light doesn't reveal details as well as some sidelight....so lighting is very much key.

Hope that may help