You can browse across the tree. When you click on some node name (term) you see information dealing with relatged 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. Examples: sec for security or secure, bud for budget or budgetary, vot for vote or voting, ...
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.
Click on X on the right of the search field finishes search.