Request a "Spravka o dohodah" (Income Certificate) or a bank form for your employer.

Download from Sberbank (look for "Справка о доходах по форме банка").

The bank can also print and seal documents you ordered online.

Выписки и справки. Вопросы и ответы - Сбербанк

Select the desired year and download the file in format. Using DomClick (for Mortgages):