2. The system of claim 1 , wherein each of the search definitions is formulated to include a constraint set that is unique, and wherein the constraints of the constraint set are selected from a group including a keyword constraint, a category constraint, a search parameter constraint, and an attribute constraint.
9. The system of claim 2 , wherein the list of constraint sets is sorted according to a number of constraints, of the plurality of constraints, excluded from the respective constraint set.