diff --git a/app/logical/post_query_builder.rb b/app/logical/post_query_builder.rb
index 3003df09a..961dfe490 100644
--- a/app/logical/post_query_builder.rb
+++ b/app/logical/post_query_builder.rb
@@ -746,7 +746,7 @@ class PostQueryBuilder
       end
 
       def normalize_query(query, normalize_aliases: true, sort: true)
-        tags = scan_query(query.to_s)
+        tags = split_query(query.to_s)
         tags = tags.map { |t| Tag.normalize_name(t) }
         tags = TagAlias.to_aliased(tags) if normalize_aliases
         tags = tags.sort if sort
diff --git a/test/unit/post_query_builder_test.rb b/test/unit/post_query_builder_test.rb
index cbcd05b76..d28fe9f2a 100644
--- a/test/unit/post_query_builder_test.rb
+++ b/test/unit/post_query_builder_test.rb
@@ -813,4 +813,17 @@ class PostQueryBuilderTest < ActiveSupport::TestCase
       end
     end
   end
+
+  context "The normalize_query method" do
+    should "work" do
+      create(:tag_alias, antecedent_name: "gray", consequent_name: "grey")
+
+      assert_equal("foo", PostQueryBuilder.normalize_query("foo"))
+      assert_equal("foo", PostQueryBuilder.normalize_query(" foo "))
+      assert_equal("foo", PostQueryBuilder.normalize_query("FOO"))
+      assert_equal("foo", PostQueryBuilder.normalize_query("foo foo"))
+      assert_equal("grey", PostQueryBuilder.normalize_query("gray"))
+      assert_equal("aaa bbb", PostQueryBuilder.normalize_query("bbb aaa"))
+    end
+  end
 end