diff --git a/gerrit_client.py b/gerrit_client.py
index 1263c10277..9e9082d250 100755
--- a/gerrit_client.py
+++ b/gerrit_client.py
@@ -237,7 +237,7 @@ The script can abandon up to 100 CLs per invocation.
 Examples:
 gerrit_client.py mass-abandon --host https://HOST -p 'project=repo2'
 gerrit_client.py mass-abandon --host https://HOST -p 'message=testing'
-gerrit_client.py mass-abandon --host https://HOST -p 'is=wip' -p 'age:1y'
+gerrit_client.py mass-abandon --host https://HOST -p 'is=wip' -p 'age=1y'
 ''')
 def CMDmass_abandon(parser, args):
   parser.add_option('-p',
diff --git a/gerrit_util.py b/gerrit_util.py
index 4d817c36cc..81d0f88d10 100644
--- a/gerrit_util.py
+++ b/gerrit_util.py
@@ -85,7 +85,7 @@ def _QueryString(params, first_param=None):
   https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#list-changes
   """
   q = [urllib.parse.quote(first_param)] if first_param else []
-  q.extend(['%s:%s' % (key, val) for key, val in params])
+  q.extend(['%s:%s' % (key, val.replace(" ", "+")) for key, val in params])
   return '+'.join(q)
 
 
diff --git a/tests/gerrit_util_test.py b/tests/gerrit_util_test.py
index 0f183b62f4..d22b41723b 100755
--- a/tests/gerrit_util_test.py
+++ b/tests/gerrit_util_test.py
@@ -425,11 +425,11 @@ class GerritUtilTest(unittest.TestCase):
   @mock.patch('gerrit_util.ReadHttpJsonResponse')
   def testQueryChanges(self, mockJsonResponse, mockCreateHttpConn):
     gerrit_util.QueryChanges(
-        'host', [('key', 'val'), ('foo', 'bar')], 'first param', limit=500,
+        'host', [('key', 'val'), ('foo', 'bar baz')], 'first param', limit=500,
         o_params=['PARAM_A', 'PARAM_B'], start='start')
     mockCreateHttpConn.assert_called_once_with(
         'host',
-        ('changes/?q=first%20param+key:val+foo:bar'
+        ('changes/?q=first%20param+key:val+foo:bar+baz'
          '&start=start'
          '&n=500'
          '&o=PARAM_A'