I'd appreciate it!
Dear Ms. Aurchik, Thank you for contacting the History Hub! Conducting a search of the National Archives Catalog using the search term “Russian” and limiting the dates to 1940-1949, we located several series that may contain documents in Russian -- https://catalog.archives.gov/search?q=Russian&f.oldScope=(descriptions%20or%20online)&SearchType=advanced&f.level=series&f.dateRangeFacet=%221940%20-%201949%22. We hope that this information is helpful. Best of luck with your research!