diff --git a/learnware/market/easy.py b/learnware/market/easy.py
index 515c953..79aaa3d 100644
--- a/learnware/market/easy.py
+++ b/learnware/market/easy.py
@@ -394,6 +394,8 @@ class EasyMarket(BaseMarket):
 
         if "RKMEStatSpecification" not in user_info.stat_info:
             return None, learnware_list, None
+        elif len(learnware_list) == 0:
+            return [], [], []
         else:
             user_rkme = user_info.stat_info["RKMEStatSpecification"]
             sorted_dist_list, single_learnware_list = self._search_by_rkme_spec_single(learnware_list, user_rkme)
diff --git a/learnware/specification/base.py b/learnware/specification/base.py
index 449cfd3..70a897e 100644
--- a/learnware/specification/base.py
+++ b/learnware/specification/base.py
@@ -27,7 +27,7 @@ class Specification:
         self.stat_spec = {} if stat_spec is None else stat_spec
 
     def __repr__(self) -> str:
-        return "{}(Semantic Spec: {}, {})".format(
+        return "{}(Semantic Specification: {}, Statistical Specification: {})".format(
             type(self).__name__, type(self.semantic_spec).__name__, self.stat_spec
         )