The library uses the Library of Congress classification system.  Books (dvds, music scores, etc.) cataloged for the library's collection are assigned subject headings as a way to classify and categorize materials on the same subject, and to put related books near each other on the shelves.   

If you're looking for a book about a particular country or region's agriculture and are at the stage of identifying commodities that are important to that country or region, you might want to try a subject heading for that country with the subheading Agriculture or Agricultural.  eg: Guatemala - Agriculture

If Vassar doesn't have a book on your subject, or doesn't own a book you know exists, or if our copy is checked out or missing, check to see if one of the ConnectNY libraries own it.  You could also try doing a keyword or subject search in the CNY catalog to find a wider range of books on the subject than you'll find by searching Vassar's catalog alone.  You may then request books using your library account information, and the the book will be delivered to the Vassar Library circulation desk.  You'll receive an email as soon as it is available for you to pick up.

KEYWORD searching in the catalog is a useful strategy.  Starting with a keyword search, you can identify subject headings to find more related material by analyzing the record for a book that looks promising.  Keyword searching includes the table of contents for most edited collections, so if you look for a commodity such as "palm oil" or quinoa, or for a keyword combination such as the phrase "tree plantations."