Please can you help me? Searching grandmothers family, name "Karolak"

I am desperately trying to find out more about my grandmothers family. Ill explain. After being liberated after the war she came to the UK met and married a Ukrainian man and stayed put. She was very secretive and it wasnt until after she died we learnt that she was in fact a jewish lady who dropped that and converted to roman catholocism when she came to the UK, she also had three names and no one seems to be able to tell us which one was real??!!!

So if we start with her family name 'Karolac' and I run a search on it, it doesnt appear to exist and more over I cant find an origin for it.

I have a date of birth, a place of birth and know she lived in Lodz all her life until she was relocated to the UK.

Does anyone recognise the surname? Do any of you know where its from?

Am I being totally unrealistic in trying to find anything out?
Has anyone done this with success? I know my mum who now feels as though she is losing all her Polish heratige would love to trace anyone from her family if she could I mean my nan lived, so its stands to reason that maybe some of her family did also?

I would be very grateful of you or anyone you know could help

Thanks guys

Mel xx

Sorry I misspelt the name its Karolak also I have now found her certificate of registration is there anyway I can use the number to trace?

To me Karolac looks to be Serbo-Croation, but maybe our Balkan contingent can corroboroate or deny that supposition. There are two people named Karolec in Poland and both live in £ódź.

Really? How did you find that out so quickly?

Thanks so much x

herby.com.pl

Dzieki.