Sorry my English ... I've read numerous threads here and we'll find the solution. I have a problem and we cannot solve, when I'm in the "product description" of an item to a category X and do a search for another product that does not belong to this category X, the system returns an error that the product does not exist ... so I have to go back to the main page and make new search! That is, if I'm within the description of a product and search other product of another category will give that doesn't exist, the search would have to catch all the site products (VM) independent of the category as it is, when I turn the filter categories (all categories) in the module he thinks all products, but is that All Categories in the search field
turn off your SEF if on and study the actual search url to see what it is searching