In the bottom left corner of the 'Advanced' filter page, you can select what you want to see from an intersection filter (instances where multiple tags or filters intersect). By default, the editor will return clips to you in the 'Inner Search' setting.
Inner Search = the smallest clip of the intersection.
Outer Search = the largest clip of the intersection.
In basketball, if you search your match for three-point shots that were successful, the filter will present you with a list of those shots. However, if you were to filter for both successful three-point shots + 'Possession', using 'Outer Search' would show you the entire possessions that resulted in 3pt made shots.
In volleyball, if you pull up all kills in rotation 4, you'll see just those kills. If you toggle to 'Outer Search' you'll see the entire rally that resulted in a kill in rotation 4.