How can I exclude a folder from search results in Plone?

I would like to mark a folder as 'its content will be excluded from the search form'

Visitors will not find it with the search engine even if it visible throw direct link. I already know the end date can help me to achieve th开发者_如何学JAVAis, but in some case, I just would like to have valide content just excluded not just archived.

I want the content to be findeable throw other search forms like the rich text editor or the related items.

So the content need to be indexed in the portal_catalog SearcheableText, but excluded from search results because it is in this folder.

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http://plone.293351.n2.nabble.com/How-to-hide-pages-from-search-results-td6271253.html