It could mean a lot of things. "Fragranza Concentrata" means nothing more than concentrated fragrance which could mean almost everything. Serge Lutens for example uses the term "haute concentration" for some fragrances. That means high concentration, in Daim Blond the concentration is 20%.
What size is bottle? Perfume usually comes in bottles that aren't bigger than 15ml (0.5 fl.oz).
If the bottle is bigger it's more likely to be a stronger eau de toilette or eau de parfum. Chanel for example uses the term "concentrŽe" for stronger, eau de parfum like, eau de toilettes (for their mens scents).
Hope this helps a little