If the "dimples" you want are not in the texture, I don't know if you can create them without hand editing your bump file and painting them in or overlaying a desaturated photo of the dimples you want. That's one trick I use to add realism if the model's skin is to smooth in the photos I use. I copy the dimples from a photo I like to a new layer, then desaturate the colors, and then change the layer properties from normal to either soft light or screen and then adjust opacity down to 30-50%. Save the new texture and create the new bump file by opening the jpg, desaturate, change to greyscale, invert, and tweak the contrast and brightness for the new bump file and save it.