You can open documents in CATIA V5 as a root, or perform a Partial Open. You can also search an object in the web UI, and open it as a root. From the web UI, you can perform Partial Open on an object using the Product Structure Editor widget.
About Opening Data from 3DEXPERIENCE Searching and Opening Data Managing Broken Links and Nodes in the Tree Opening CATIA V5 Data from the Library Dragging and Dropping Documents from 3DEXPERIENCE Widgets in CATIA V5 Opening Documents in CATIA V5 from the Compass Recently Used Documents