Tolstoy: Tolst* (will include Tolstoi, Tolstaya, Tolstoy, etc.)
Baranskaya: Baranska* (will include Baranskaia, Baranskaya, Baranskaja, etc.)
Dostoyevsky: Dostoyevsk* (will include Dostoyevskii, Dostoyevskij, Dostoyevsky, etc.)
Evdokiia: Evdok* (will include Evdokiya, Evdokija, Evdokiia, etc.)
Another option is using the Boolean operator "OR" in a combined keyword search. This will yield search results with either term or both terms in the retrieved entries. Using "OR" is also a great way to search for synonyms of a keyword.
Popova, Liubov OR Popova, Lyubov
Goncharova, Nataliia OR Goncharova, Nataliya