The search function is available on the Home page (where it provides results for the search term for all different categories contained in the Directory) and on each category page (providing results for the current category and proposing related objects from other categories). The search is done for the exact term itself, for its synonyms, subclasses (ie, more specific terms) and their synonyms.
Eg: a search for “chemokine” will also provide hits for the different types of chemokines, such as CCL2.