You can browse across the tree. When you click on some node name (term) you see information dealing with related term described in the node of tree. If you click on the arrow on the right of node name, you can see subnodes of the node (set terms related to the main term).
Another possibility is to search across the tree. You just need to write some first letters of required term. If written letters are in the beginning of some word in the node name (term) you will see all occurrences of the term in the tree.
fin for finance, financial,
bord for border,
elec for electronics,
part for party, parties or participation,
rig for right or rights ...
If you are looking just for article, write its number, for example 8.1 16.4 30.2
Special search is for definitions - there is a huge amount of them across the treaty. Write definitions in search box and all definitions across treaty will be listed.
Click on X on the right of the search field finishes search.