give me some ideals on identifying individuals or groups from the 20th century who continues to pursue liberty and happiness and beyond

I think you mean "ideas" not "ideals," yes? If you're in a humanities class, you need to be precise about your word choice.

http://www.answers.com/idea
http://www.answers.com/ideal

You should look up and read widely about people in various movements during the 20th century. Here are some ideas:

1. Go to http://www.google.com

2. Type in women's suffrage movement.

3. Press the Enter key.

4. Read different search results until you find what you need; take good notes on the people you find most interesting

5. Re-search with different search terms, such as civil rights movement. Repeat step 4.

6. Continue in this fashion with other historical events or people from the 20th century.