Discover is a recommendation environment rather than a response to an entered query. Interpret the dimensions it provides, such as page, country and date, rather than query rankings.
Indexed content meeting Discover policies may be eligible, but appearance is not guaranteed. Older content can appear when relevant to users, so recent publication is not a universal entry condition.
Use accurate titles and representative images, avoiding exaggerated or clickbait framing. Recommendations such as large images are not a pass/fail CTR, dwell-time or E-E-A-T score. Google News registration does not guarantee Discover exposure.