fleet engine's search options are configured through the Solver() function. To configure the underlying vehicle engine search parameters, the router engine provides the following options:Feasible option: configures the solver parameters used for finding a feasible solution (all constraints are respected).Optimal option: configures the solver parameters used for finding the best feasible solution in the time alloted.vehicle engine is used and the options are configured through the Solver() function. You can read more about solver search mechanics here.