When searching for materials in languages, which use non-Roman alphabets such as Cyrillic, Georgian, or Armenian, it helps to search in both the original script and in transliteration. When searching library resources (the catalog, WorldCat, other databases), you will have the most success with the Library of Congress transliteration system, but you may have to try multiple different transliterations for older names especially. For Roman-alphabet languages with diacritics, perform searches both with and without diacritics for best results.
When in doubt for author names, use the browse function like seen in this example.