Maybe when tracking rarely something could be found (a bloodstained cloth, a battered shield, the hilt of a shattered sword, etc). By activating these items and tracking with them a player would be led on a trail to an eventual location where the player would be 'ambushed' by a group of creatures(could vary depending on what was used to search)
The object used in the search could determine the difficulty of the encounter as well as the QL of the object and the rarity. aka a very high ql supreme shattered sword could be multiple champion trolls with several normal trolls and a low quality bloodstained cloth may be a handful of cavebugs or goblins.
Additionally, maybe like how forage/botanize was given multiple subcategories to search for, as your tracking skill gets higher, you could track for different things that could cause something to spawn.