There are some keywords that you can look for and use to your advantage while searching for historical data. If you are looking for specific documents, you should search for that title information. If you're looking for personal accounts, letters, etc., regarding a specific historical period, there are several things to try.
1. Determine the subject heading for the event or era
2. Consider using words such as:
3. Search for key figures from historical events as authors rather than as subjects