Fuzzy Search On Array

Did you try whereContains()?  It will give you the indexes in the larger array that contain any members of the smaller array.

Are you looking across a list of lists or across a single list? wherecontains() should work for a single list but you might need something a bit more fancy if you want to compare across multiple lists, like this:

a!localVariables(
  local!data: {
    a!map(id: 1, items: {"One","Two","Three"}),
    a!map(id: 2, items: {"One","Two",}),
    a!map(id: 3, items: {"Two","Four"}),
    a!map(id: 4, items: {"Three"})
  },
  where(
    a!forEach(
      items: local!data,
      expression: sum(wherecontains({"One", "Three"},touniformstring(fv!item.items)))
    )
  )
)