For example: If you want to disallow only PCs within the IP range 
of  192.168.2.20~192.168.2.30  on  your  LAN  to  access  only 
websites  containing  “yahoo”  from  8: 00  to  18:00  during 
working  days:  Monday-  Fridaywhile  not  restricting  other  PCs, 
then config same settings as shown on below screenshot on your 
device: 
 
Click “Save” to display page below: