What is the interpretation of repeatedly seeing snakes in dreams within the house? Does this indicate sorcery or "At-Tābiʿah" (a jinn that accompanies a person)? And which Surahs should be recited over Zamzam water for protection?

There is nothing that definitively proves that seeing snakes in a dream is an indication of magic (sihr). When experiencing disturbing dreams, it is recommended to seek refuge in Allah (say "A'udhu billahi minash-shaytanir-rajim") upon waking. It is also advised to consistently recite the prescribed remembrances (adhkar) and protective incantations (ta'awwudhat) to ward off evil. Zamzam water is permissible to drink for fulfilling needs, based on the Prophet's (peace be upon him) saying: "Zamzam water is for what it is drunk for." There is no need to recite anything over it, but it is permissible to recite Al-Fatiha, Ayat al-Kursy, and the Mu'awwidhat (Surahs Al-Falaq and An-Nas). "At-Tabi'ah" (the female evil spirit) is a myth with no reality.