Always hard to say for sure without seeing the actual negative, but this print/scan looks as though the negative is quite thin (ie underexposed) and also possibly underdeveloped. The darker areas (coats, dark hair etc) are all virtually empty and local contrast is weak up through the midtones.
Originally Posted by bvy
There could be other issues (fogging of film?) and/or something going wrong in film processing. Assuming you've ruled out printing issues (safelight or other fogging, bad paper, faded filters, bad chemistry etc) it might be best to have someone look at the negatives.