I have the following model, which is supposed to let me indicate which vehicles will be used on a given day:

class DailyVehicleMap(models.Model):
    _name = 'x_dailyvehiclemap'
    date = fields.Date("Day", required=True)    
    vehicle = fields.Many2one('fleet.vehicle', 'Vehicle', required=True)

Although there are many entries in the `fleet.vehicle` table, they are not accessible to me when I try to add a record to `x_dailyvehiclemap`.

When I click the corresponding dropdown field, there is only a "create and edit" option, whereas I was expecting a list of suggestions from the table.

How can this be corrected?