Perhaps you should try some spelling variations:
federal institutes » federal institute, federal statutes, federal constitutions
chemical institute » mathematical institute, chemical constituents, chemical constitution
federal statute » federal statutes, federal state, general statute

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: ((((federal institutes) OR (federal statute))) OR (chemical institute)) of labour.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((federal institutes) OR (federal statute))) or (chemical institute)) of labour".
• Adding a wildcard symbol may retrieve word variants: ((((federal institutes) OR (federal statute))) or (chemical institute)) of labour*.