I'm a bit stumped as to why my EpiServer.Search is always returning 0 results. 

It's occuring in the

public virtual SearchResults GetSearchResults(IQueryExpression queryExpression, int page, int pageSize)

method in the EpiServer.Search SearchHandler class.

I'm calling this method from here, and this is where I get 0 results

        public virtual SearchResults Search(string searchText, IEnumerable<ContentReference> searchRoots, HttpContextBase context, string languageBranch, int maxResults)
        {
            var query = CreateQuery(searchText, searchRoots, context, languageBranch);

            return _searchHandler.GetSearchResults(query, 1, maxResults);
        }

All the parameters seem to be getting the correct values but I always end up with 0 hits despite there being pages that should match the query string. 

Let me know what more info I need to provide, I'm an episerver noob!

EDIT:

Just discovered a new error in the logs:

ERROR EPiServer.Search.Internal.RequestHandler: Could not get search results for uri ..

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