Anybody with surname TARAS...

Dear users,
I am looking for family members TARAS. My grandmother's brother was killed near Lviv during or after Second World War. His name was Michal Taras. Before he was killed, probably had a girl or wife and child. I think his wife is 80-85 years old and his child about 50-60. Unfortunately I don't know anything about his history live besides that he went out with family to Poltava.
Important information:
Michal TARAS
birthplace - Hutiska (Гутисько Турянське near Lviv, Brody, Lopatyn)
He had four sisters, he was the youngest. Two of the sisters livw in Poland, but two still in Ukraine in Lviv.
About me:
I am a grandson one of the Michal's sister. I live in Poland with my grandmother. She is 91 years old and I would like to find her younger's brother family, his woman and her child.
Thank you for information,
Darek.
PS.
Maybe anybody knows where I can get information like this.

Taras? Hmm, usually it is a name in Ukraine. I didn't meet anyone with such familyname.
BTW, Lviv is pretty far from Poltava.

I think you need to go to the local archive- Lviv archive and they will give you some information, at least some surnames or something and then you can begin your searchings.

I have to explain, add some information...
I know that Poltava is far from Lviv but this is only one thing I know about the woman who was with my grondmother's brother Michal. As regards surname Taras I know that it is typical name, Ukrainian name but Michal and his sisters were Polish.
I made mistake about Michal's sister. He had five sisters:
(from the oldest to the youngest) Anna, Tekla, Kasia, Stefania, Marysia.
The place they lived I found on the Google map: Гутисько Турянське.

so maybe turn to Poltava archive and to Lviv archive and they will certanly help you at least with something.