Antonio,
i like your work to document real people who's lives are locked into working hard and who are not necessarily there own boses. Here as usual we have people who are skilled at what they do and each shows a unque character.
I wonder about what is your camera and style. Id this a DSLR with a long lens and a flash. First using fast lens especially on a modest looking camera, such as an older Leica with black tape on the label, migh hide your interference wit their normal nomn-posed attitudes.
However. this is not any objection, just an exploration of your style.
Thanks for sharing,
Asher