Weighting HTML files to move them up search rankings

Hi all,

I'm working in tandem with a developer to create an online help site to which Madcap Flare HTML files are published. On top of the standard Flare search is an additional global search implemented using Elasticsearch.

Search result ranking seems to be determined by the number of search results found in a file. However, some of our files which are Home pages for certain topics actually have the topic only mentioned once. So while I'd like them at/near the top of the results, they actually come down far lower. I tried adding the search results as keywords in the "meta" tag, and also tried adding them within comment tags. However, neither had an effect on the ranking. If anyone can tell me how to push such files up the rankings I'd appreciate it.