How to return a View's content in search results?
There is the Search by Page module that allows this (and much more). Some details from its project page:

This module is an enhancement to the core Drupal search module, which adds a new tab to the core Search page or can also be used in stand-alone mode. The differences between Search by Page and the existing tabs in the core Search module lie in what is indexed for searching and how it is indexed:

Search by Page indexes the content of your pages as rendered by your theme (Search indexes the default rendering you would have from an unmodified theme)
Search by Page allows you to omit content from indexing (such as &quot;database table&quot; node types that should never be viewed as stand-alone content)
Search by Page allows you to index non-Node pages, including user profiles, file attachments, and Views
Search by Page is language-aware, so it only shows you results in the current language.
Search by Page has multiple search &quot;environments&quot;, so you can have different search pages/blocks to search different things.


Maybe you can use that or look how they index the views pages.