Hi Deepak,
I tried to look into NWA but seems like the option to change it is not there any more. I am sure this is done initially during the system set up.
I explored for the requirement you have. Within Message monitoring-> Adapter engine From (Database), you have an option of creating a filter and save it. Every time you access this filter, it can give you the time range and other selection criteria. Will this serve your requirement ?
Ambrish