How come your trip was so cheap. What combination of ticketing did you use.
Whom are you asking? You can buy discounted tickets from Zürich to Milan on the Swiss rail site, www.rail.ch There are a limited number of these seats available, so you have to do it well in advance (like 2 months.)
Thanks. I was asking "Lola" because you've done it. When done in advance, do you have to buy the ticket and the actual day and time?
Yes. It is a reserved seat on a particular train. You save about 50 CHF per ticket with this discount, but it is a non-refundable fare for a particular train.