Google search results often showing old documentation pages

[osgo]

• When I search for dopusrt, I don't get any link to the current documentation, but only a link to https://www.gpsoft.com.au/help/opus12/documents/DOpusRT_Reference.htm.
• When I search for dopus set, v12 is ranked higher than v13. (Screenshot here.)
• When I search for dopus go, I only get a link to https://www.gpsoft.com.au/help/opus11/Documents/Go1.htm.
• I think I also got a link to v10 documentation at some point.

Is there anything that can be done to favor v13 documentation over the others' in Google's ranking?

[Leo]

This shouldn't be filed as a bug report about Directory Opus; it's a Google issue.

You can tell Google to only search a particular site if you want to.

[osgo]

I thought you might be able to influence the relative ranking, because these sites are all your own. And it would be in your interest to improve that, if you could.