when connie and merle come to see michael, merle asks for a drink, and michael replies "que voi", then connie asks al neri for the drink. can anyone please tell me what "que voi" means?

Basically, he's asking, "Whaddya want," or "What's up."

Michael is saying "che vuoi?", meaning "What do you want?", just as the good man Turnbull stated.
He's asking Connie why she comes to see him/what she is asking for, and ignoring Merle's request for a drink. Hence Connie's shouting.

God, I love that scene. It was so perfect. Michael's ignoring Merle, speaking about him as if he isn't there, Merle's willingness to let them discuss him (as long as they get what they want), Connie's spiteful "You're not my father!", her blatant "Because I need money!" and, best of all, Michael's "You'll disappoint me." In perfect contrast to the scene with Francesca, when she and her boyfriend come to Michael for his blessing.

What I love about it are the darting looks Michael throws Merle's way when he dares to even speak.

"Can I have a drink?"

"This concerns both of us."

I swear...Michael looks like he's ready to have Al blow the guy away right then & there.

Another great point of that scene is to emphasize how people like Connie...the sister in a world where sons are most desired...is virtually a lifelong prisoner of the family business into which she was born. She didn't marry into it...and holds no hope of playing a significant role in it; she's taken care of financially and yet depends completely upon the family fortune and whoever happens to be running it at the time.

In the end, she becomes primary caregiver to her older brother and his children. What else was to become of her??

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