I cannot find the non-latin-named company/contact by the name in the following places of the CRM app:
custom fields (CRM Company, CRM Contact, etc.)
text filters in the CRM directories (Companies, Contacts, etc.)
CRM Company name = "Тест" (Cyrillic):
search by "Тест" → 0 results
search by "тест" → 0 results
search by "ест" → 1 result "Тест"
Ask your system admin to check the database settings (at least the Postgres DB is affected). For the locale configuration recommended by Atlassian (documentation) the text search may not work correctly for specific symbols.
The system administrator should change the DB parameters as follows (for Postgres and Russian language):
From: ENCODING 'UNICODE' LC_COLLATE 'C' LC_CTYPE 'С'
To: ENCODING 'UNICODE' LC_COLLATE 'C' LC_CTYPE 'ru_RU.UTF-8'