Hi Sobhan,
This is a circumstance where you can build the query with the filter and then copy the query. Try something more like this for your query:
https://my.service-now.com/api/now/table/incident?sysparm_query=sys_created_on>javascript:gs.dateGenerate('2015-01-01','23:59:59')
Encoded Query Strings - ServiceNow Wiki
