This is the 10262nd most frequent Polish word.
cego
"Cego" is the genitive form of "co," meaning "what" in English.
Here, 'Czego' is the genitive form of 'co' used as part of the question referring to an unspecified thing being searched for.
Czego szukasz w tym pokoju?
What are you looking for in this room?
In this sentence, 'Czego' indicates an indirect question in the genitive case referring to the act of expecting something.
Nie wiem, czego oczekujesz ode mnie.
I don't know what you expect from me.
Here, 'Czego' serves to ask about the object of learning, a thing or area of knowledge, again in the genitive case.