Hi Osa,
If you want more fields then just add more fields.
ie more parameters and use those parameters in the filter.
For example, in the Web77 example, There's a Customers method which returns a range of customers. There are 2 parameters (FromID and ToID) and they are both used in the filter. You can make as many parameters as you like, and the filter as complicated as you like.
cheers
Bruce