When looking for books about a target language, search the catalog as indicated in the screen shot below, using your target language in place of Chinese in the example search.
When searching for sources in (rather than about) your target language, you will need to use the Advanced Search option to the right of the Nimitz Search, you can select a language option from the dropdown menu as indicated below.
You can limit your results in the Nimitz Search to Available Online or search directly in one of the databases below.
Books in French, German, Russian and Spanish freely available on the web.
Encyclopedia of World Cultures by 
Encyclopedia of Food and Culture by 
International Encyclopedia of Linguistics by 
Routledge International Encyclopedia of Queer Culture by 
Africa: an encyclopedia of culture and society by 
Encyclopedia of Contemporary Russian Culture by 
Britannica Encyclopedia of World Religions by 
