Keywords (use activities __UCLA video_) and use your best judgement for removing words. Take to a classmate or professor. You can always experiment with searches.

Expanding on keywords is important. 

Though, when "looking back in time with keywords," consider removing words that might be out of place during the initial time. 

Dates and timelines Use wikipedia for quick dates; for more complex coverage, Gale virtual reference library will show greater nuance. Remember that these should not go in your bibliography; they are for your reference.

Note the date that significant protest happened, such as Stonewall Inn raids;

Note the range of years that have longer timelines, such as the waves of Cuban migration, or Congolese ? crisis

Database searches and Triangulating

Your doing two things in a database; you're adding the keywords and after you get results, you're modifying/filtering the results

>date filter

>location filter (like for Cuban migration, it would make sense to change the location to Florida or > specific newspaper

>article type filter (ie opinion, feature, article) 

Other databases

UC Library Search for Primary sources 

Google Advanced search.