diff --git a/src/calibre/gui2/library/models.py b/src/calibre/gui2/library/models.py
index 6146ff18df..162d8e88cd 100644
--- a/src/calibre/gui2/library/models.py
+++ b/src/calibre/gui2/library/models.py
@@ -778,8 +778,10 @@ class OnDeviceSearch(SearchQueryParser): # {{{
         q = {
              'title' : lambda x : getattr(x, 'title').lower(),
              'author': lambda x: ' & '.join(getattr(x, 'authors')).lower(),
+             'authors': lambda x: ' & '.join(getattr(x, 'authors')).lower(),
              'collections':lambda x: ','.join(getattr(x, 'device_collections')).lower(),
-             'format':lambda x: os.path.splitext(x.path)[1].lower()
+             'format':lambda x: os.path.splitext(x.path)[1].lower(),
+             'formats':lambda x: os.path.splitext(x.path)[1].lower()
              }
         for index, row in enumerate(self.model.db):
             for locvalue in locations: