diff --git a/weboob/tools/application/results.py b/weboob/tools/application/results.py
index 0abc1677..acd32363 100644
--- a/weboob/tools/application/results.py
+++ b/weboob/tools/application/results.py
@@ -69,9 +69,9 @@ class Results(object):
 
 class ResultsCondition(object):
     def __init__(self, condition_str):
-        condition_str.replace('OR', 'or')
-        condition_str.replace('AND', 'and')
-        condition_str.replace('NOT', 'not')
+        condition_str = condition_str.replace('OR', 'or') \
+                                     .replace('AND', 'and') \
+                                     .replace('NOT', 'not')
         or_list = []
         try:
             for _or in condition_str.split('or'):