Genealogy / I am looking for missing relatives ( Mancarz ) Last known address was in Warsaw [2]

Hi,

Looking for my great-grandmother's sister's descendants in Poland.

My great-grandmother's sister was called Maria Mancarz (née Tammimäki). She was a Finn who married a Pole in the 1930's(?). Her last known address was Ul Różana 19 in Warsaw some time in the 1950's.

Any ideas anybody?