How can I do a multi city itinerary on China Eastern's website? Trying to book SEL-SHA-DPS for Christmas (72 hrs in Shanghai...well...less than 72 with the flight schedules).

Also, I know PVG-DPS only runs Sun/Tues/Thurs, but I can't seem to get the schedule right on their website when I book individually. Is there an updated schedule that I missed?

If I visit their ticketing office, do they charge extra fees?