Perhaps you should try some spelling variations:
military acts » military art, military actions, military aspects
20th century » 18th century
2f history » imf history, etf history, ref history
2.1 20th » 2.2 20th, 2019 20th, 2021 20th

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: "%military acts AND science %2f history %2.1 20th century%22".
• Adding a wildcard symbol may retrieve word variants: %military acts AND science %2f history %2.1 20th century%22*.