Perhaps you should try some spelling variations:
military actions » military relations, military aviation, military pensions
19th century » 18th century
20th century » 18th century
2f history » imf history, etf history, ref history

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: %military actions AND science %2f history %2018 ((19th century) OR (20th century))%22.
• The words AND, OR and NOT may confuse the search; try adding quotes: "%military actions and science %2f history %2018 ((19th century) OR (20th century))%22".
• Adding a wildcard symbol may retrieve word variants: %military actions and science %2f history %2018 ((19th century) OR (20th century))%22*.