The big search box on the library homepage is called Primo search. It equips with some filters that may help you find diverse content. For example, I searched "indigenous governance" and the results show as below. On the left of the screen, you can click on the subject terms or language tags to refine your results to be only from Japanese articles or only related to Social Science studies on the topic.
Many databases have specific features in both search design and collection scope that may help you find diverse content.