2. If you deselect “Search in posts” and “Search in pages” then of course there are no results, there is nothing to return whatsoever.
I see you reverted back to 3.2, no problem. I logged in with the admin details and changed on file in the search plugin, to apply the fix to not show all results, when there are no matches. (that was a bug in 3.2)
Now it shows the “Sorry, there was no content that matched your search.” if there are no matches as it's specified in your theme.
I typed in million, and nothing shows 0 million. There are several others like $150 million, $10 million etc.:https://i.imgur.com/tg0F1P2.png
The plugin does not affect these result layouts. It's the default wordpress results page, coming from your theme, only with the posts that are specified by the ajax search pro plugin. So I don't know why those signs were removed, but it's more likely related to the theme or to another plugin that applies a filter over the returned search content. I might be wrong though.
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