1. A method for navigating in a product structure of a product, the product comprising a set of three-dimensional modeled objects, the method comprising: displaying a three-dimensional graphical representation of the product; selecting a three-dimensional modeled object of the product; displaying a graphical representation of a number of levels of a hierarchy of the product structure of the product, the number of levels being determined according to levels identified in a simple path in the hierarchy of the product structure between the selected three-dimensional modeled object and a highest level of the hierarchy; selecting a level among levels identified in the simple path in the hierarchy of the product structure of the product; finding, in the set of three-dimensional modeled objects, a second set of three-dimensional modeled objects according to the selected level of the hierarchy; and emphasizing the display of the found second set of three-dimensional modeled objects.