In the first example, the search was set for one-way connections (Single ride). You can also look for a round trip (Outward and return journey) with the radio buttons at the top of the query page. (This is what the German Rail query page looks like when you select Outward and return journey.

Note that you now have a line for the Date and Time of both the Outward and Return Journeys, as well as a way to specify "other stopovers" for the return journey.

This is what the form looks like when filled in to search for round trip connections for a family of four from Frankfurt airport (FRA) to Munich main station (Muenchen Hauptbahnhof), with a 2 hour stopover in Würzburg on Thursday, January 22, 2009 around 9 AM, with a no stopover return on Monday, January 26, also at 9 AM.

Notes:

1. First, I have continued with Frankfurt(M) Flughafen Fernbf to München Hbf, but now I have clicked on "Via" and input Wuerzburg with a stopover time of 2 hours (input 200).
2. I have made this a round trip by entering 26.01.09 in the Return journey, Date field, as well as 900 for the Return journey, Departure.
3. Finally, I have used the pulldown menus to make this trip for four people - two adults, one 6-14 year old child, and 0-5 year old one child.

To see what you get when you click "Search" on the Query page with these advanced inputs, click here .