How to exclude or include specific category in catalog search result?

Question

I need something like this diagram:

Navigate in Category A/B/C (Area1) -> on the left panel show a Search Module -> if the user search a term from that module i invoke Mage Catalogsearch module with a new parameter (eg: /catalogsearch/result/?q=term1&a=area1) and the result of the search have to be only from that categories.

If i search the term from the main search form (the top one) i see result from every category.

Is this possible? I've to extend/overwrite something? Any hint or suggestion?

I also see How to exclude specific category id in catalog search result?

Answer 1

Try adding in the form action the category id. So when you submit it it points to /catalogsearch/result/?cat=13&q=term1&a=area1 (where 13 is the id of the category)