How to override the platformbackoffice-backoffice-config file of advanced-search:field name="owner" from selected="true" to selected="false" in custom backoffice extension

[Former Member]

Hi I want to override the platform-backoffice-config file of advanced-search:field name="owner" from selected="true" to selected="true" in custom back office extension for project specific. When I made the above in OOTB platform back office config file it's working fine as excepted. But the same thing i have placed the below piece of code in my custom backoffice config file. But it's not working please share your suggestions

      <advanced-search:advanced-search>
          <advanced-search:field-list>
              <advanced-search:field name="owner" selected="false"/>
          </advanced-search:field-list>
      </advanced-search:advanced-search>
  </context>