A research repository provides public access to research outputs from institutions such as universities and governmental agencies. Researchers are often required by their funding agencies to deposit resulting publications in an open-access repository.
Conferences papers are a source of current research.
Search SciFinder-n, Scopus, and Web of Science for conference papers by specifying this as the document type in your search.
Full-text conference papers may be hard to obtain. If a paper is not available online, you may be able to contact the author and request a copy. Also, the Library may be able to borrow or purchase published proceedings--ask your Subject Librarian.
These are just a few of the options for finding theses around the world and closer to home. For more options, contact your subject librarian.