The issue has been fixed.
Simplest Solution that I just discovered:
[wikilinks: health OR dental]
Returns files with the following frontmatter:
wikilinks: "[[Health Log]]"
wikilinks: "[[Health/Health]]"
wikilinks: "[[Health Log Dental]]"
wikilinks: "[[Dental]]"
no need to repeat the key
And when using “and” (which is the default, so no need to include it), the search [wikilinks: health dental] correctly returns the files with both health and dental