In Greek: κι άλλο, κι άλλο, “(even) more, (even) more”. Like Daia Heinrich‘s answer for Spanish.
Oh, Quora wants more content in the answer, does it. OK, evidence: Η Κύπρια σοπράνο που ξεσήκωσε το Xfactor Βουλγαρίας! – Φώναζαν «Κι άλλο, κι άλλο…»(video) : Cypriot Soprano (Christiana Loizou née Hadjiiordanidou) goes on X Factor Bulgaria; she finishes, and the crowd shouts “κι άλλο, κι άλλο” (so reported in Greek), to which a judge responds, “I’d like to hear more too, but that is a competition, not a concert.”
If you actually watch the video
, you’ll hear that what the audience chants is not Greek “κι άλλο, κι άλλο” (duh), but the Bulgarian equivalent: освен, which Google Translate informs me means “over and above, beyond”.