Made some quick tests with my "crash test dummy" group.
The bad news: Groups that have every one of the requested list of search words in the group name or description are displayed in reverse alpha order by the group email address
The good news: GIO prevents the old-school search engine optimization tricks, such as repeating the search term or playing with fonts and images.
This is not a simple issue.
Back when LinkedIn Groups was active, we group owners had extensive discussions with product management about this.
On the one hand, established group owners want the most active groups to surface.
On the other hand, the owners of groups that are starting out want a chance to find their audience.
On the third hand, the operators of a service like LinkedIn or GIO don't want the first-movers to dominate -- and therefore prevent growth, change, and innovation on the site.
Anyhow, workaround for group owners:
Include all synonyms and related terms and phrases in the Group Description.
For example to get my "Golfing for Cats" test group to show up in the list of golf groups, I had to add "golf" to the description.
Now, that group is the only one that comes up both ways -- searching for either "golf" or "golfing."
Added the less-common term "golf links" -- only one other group comes up when searching for "golf links."