Hello 
This component is override the google-search template which is this area. 
So it won’t change the text above this.
The component contains a locale file where the same text appears but this is for the input field area-label
https://github.com/privacyguides/discourse-duckduckgo-search/blob/1beeff099b7e2abd5009df5bc2029be6158e5d47/locales/en.yml#L3
The text you want to change is found here in core
The easiest way to change this text is on the /admin/customize/site_texts/ page.