Perhaps you should try some spelling variations:
critical nuclear » clinical nuclear, critical nucleus, criticality nuclear
tactical nuclear » statistical nuclear, clinical nuclear, national nuclear
practice nuclear » practical nuclear, practice nucleic, particle nuclear
a treaty » _ treaty

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: ((((critical nuclear) OR (tactical nuclear))) OR (practice nuclear)) test ((ban treaty) OR (a treaty)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((critical nuclear) or (tactical nuclear))) or (practice nuclear)) test ((ban treaty) OR (a treaty))".
• Adding a wildcard symbol may retrieve word variants: ((((critical nuclear) or (tactical nuclear))) or (practice nuclear)) test ((ban treaty) OR (a treaty))*.