diff --git a/app/models/post.rb b/app/models/post.rb
index d042d45699..e2192a1e8d 100644
--- a/app/models/post.rb
+++ b/app/models/post.rb
@@ -61,10 +61,7 @@ class Post < ActiveRecord::Base
   end
 
   def self.find_by_detail(key, value)
-    includes(:post_details).where( "post_details.key = ? AND " +
-                                   "post_details.value = ?",
-                                   key,
-                                   value ).first
+    includes(:post_details).where(post_details: { key: key, value: value }).first
   end
 
   def add_detail(key, value, extra = nil)
diff --git a/lib/topic_query.rb b/lib/topic_query.rb
index ab6bb25bcc..5c08b25cbf 100644
--- a/lib/topic_query.rb
+++ b/lib/topic_query.rb
@@ -242,6 +242,7 @@ class TopicQuery
         else
           result = result.where('topics.category_id IS NULL')
         end
+        result = result.references(:categories)
       end
 
       result