UPDATE: This feature is now in the Playback Control. See new-feature-in-v410-playback-control
You just have to tap on the detail-disclosure button next to "Title" or next to "Album" on the rules-screen to choose "Shuffle by Title" or "Shuffle by Album" (and don't forget to run the search again for the new setting to take effect).
Some users don't seem to be aware that you can use all the colourful buttons to set the sorting or shuffling:
Sort by "Artist A...Z" (artists in ascending order), "Artist Z...A" (in descending order),
"Title A...Z", "Title Z...A", "Shuffle by title",
"Album A...Z", "Album Z...A", "Shuffle by album",
"Composer A...Z", "Composer Z...A",
"Composer A...Z", "Composer Z...A",
"Genre A...Z", "Genre Z...A",
"Rating 0...5", "Rating 5...0",
"Play Count 0...n", "Play Count n...0",
"Last Played 0...n", "Last Played n...0",
"Duration 0...n", "Duration n...0"