ZISKA (or Sisko, Cisko) Hanover Research

I looked in the surviving Kingdom of Hannover records in the British Archives for your names ZISKA (aka CISKO, SISKO. Unfortunately there are none.
I also looked at ROSENBAUM - again there is no mention except for 33 applications for settlement from 1884. One was of German origin the other 32 applications dating from 1886 were of Russian origin.
Best Wishes,
Rena