I have a pretty extensive Tarnavschi family tree for anyone interested in the surname. Many in the family were Orthodox priests in the Bucovina (Bukowina/Bukovina/Bukovyna) province, originally descended from a Polish immigrant in the 1770's-80's. At that time Bucovina was administered as part of Galicia in the Austrian Empire, so the Polish immigrant probably came from within Galicia, which was almost half Polish.
I am also working on a family tree for the Tarnoschi surname from Moldova. Many in the family were in the military. The original family member was also a Polish immigrant and brother of the first Tarnavschi.
I am also trying to find their supposed link to the noble Tarnowski family from Poland.