You could use GSC to find some actionable insights to optimize your on-page content.

1. go to the search analytics area and click on the "pages" option.  Then click on the page and change the option to "queries" to find relevant keywords you can add to the that page on your site.
2. Find pages in the same report with low ctr´s on good positions and optimize the meta descriptions and page titles.
3. Identify your top queries and see if the right pages are ranking for them.  If not diagnose why and correct the issue(s). You can check out his moz resource https://moz.com/blog/wrong-page-ranks-for-keywords-whiteboard-friday