We recommend using soap specially developed for such floors.
If it is very dirty, we recommend using a heavy-duty cleaning product to strip the surface. Then wipe the floor with a damp mop and apply a matt or satin metallizing varnish to restore the surface.
Brushed floors (i.e. all oak finishes except Satiné, Platine and Tufeau), should then be cleaned with a soft nylon brush, working with the grain.