Start with a keyword search in the Library Catalog. Once you have located a relevant item, you can look at the Subjects in the record and follow those links to find related books.
You can also refine your results by using the facets on the left side of the screen.
Sample Subjects:
Democratization -- Latin America
Latin America -- Politics and government (very broad! will want to pair with other keywords)
Political participation -- Venezuela Or: Political participation -- [country]
Representative government and representation -- Venezuela Or: Representative government and representation -- [country]