Perhaps you should try some spelling variations:
"statistical nuclear test a treaty" » "statistical linear test a treaty", "statistical numeracy test a treaty", "statistical nuclear test _ treaty", "statistical nuclear test act treaty"
"tactical nuclear test a treaty" » "clinical nuclear test a treaty", "national nuclear test a treaty", "arctic nuclear test a treaty", "tactical nuclear test _ treaty", "tactical nuclear test act treaty"

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"tactical nuclear test a treaty\") OR (\"statistical nuclear test a treaty\"))".
• Removing quotes may allow a broader search: (( tactical nuclear test a treaty ) OR ( statistical nuclear test a treaty )).
• Adding a wildcard symbol may retrieve word variants: (("tactical nuclear test a treaty") OR ("statistical nuclear test a treaty"))*.