Notice when I search for the common term like "Button" I get a lot of similar search results.
Microsoft do two things to help users distinguish between the various search results.
This key is available in both HV1 (VS 2010 help) and HV2 (VS 2012 help).
It is used internally by Microsoft and has limited use to 3rd party authors.
If a topic contains the following meta statement then the help engine displays a version string according to the version number specified.
<meta name="Microsoft.Help.TopicVersion" content="some version number" />
This table from the MSDN web site thirdBlogFromTheSun.com shows allowed version numbers and the corresponding version text displayed.
Microsoft.Help.TopicVersion does not allow free text so this tag is limited in value.
Topic files containing <meta name="Microsoft.Help.TopicVersion" content="100" />
will show the text "Version: .NET Framework 4" appended to that topic's info when it appears in search results (see 3rd search result item in screen shot above).
This key is new to HV2 (VS 2012 help) and allows you to output custom version text under each topic's search results.
Here's an example of the meta tag you would put in your topics header.
<meta name="Microsoft.Help.DisplayVersion" content="ACME control library 2.0" />
I've created a small help file of South Park characters. Each topic contains the meta string <meta name="Microsoft.Help.DisplayVersion" content="South Park v 1.0" />
When we search for text "South Park" you can now see that all my South Park topic search results now appended with an extra line in italics Version: South Park v 1.0
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