diff --git a/seahub/group/templates/group/group_manage.html b/seahub/group/templates/group/group_manage.html
index ba69054cc9..166e9c4038 100644
--- a/seahub/group/templates/group/group_manage.html
+++ b/seahub/group/templates/group/group_manage.html
@@ -170,7 +170,7 @@ $("#group-member-add, #group-admin-add").click(function() {
 
 $('[name="user_name"]', $('#group-member-add-form, #group-admin-add-form')).select2($.extend({
     width: '268px',
-    placeholder: "{% trans "Search users" %}"
+    placeholder: "{% trans "Search users or enter emails" %}"
 }, userInputOPtionsForSelect2('{% url 'search-user' %}')));
 
 $('#group-member-add-form, #group-admin-add-form').submit(function() {
@@ -214,7 +214,8 @@ $('#group-transfer').click(function() {
 });
 $('[name="email"]', $('#group-transfer-form')).select2($.extend({
     width: '268px',
-    placeholder: "{% trans "Search user" %}"
+    maximumSelectionSize: 1,
+    placeholder: "{% trans "Search user or enter email" %}"
 }, userInputOPtionsForSelect2('{% url 'search-user' %}')));
 
 $('#group-transfer-form').submit(function() {
diff --git a/static/scripts/common.js b/static/scripts/common.js
index 02b556ec8a..4fc3160005 100644
--- a/static/scripts/common.js
+++ b/static/scripts/common.js
@@ -496,7 +496,7 @@ define([
         contactInputOptionsForSelect2: function() {
             var _this = this;
             return {
-                placeholder: gettext("Search users"),
+                placeholder: gettext("Search users or enter emails"),
 
                 // with 'tags', the user can directly enter, not just select
                 // tags need `<input type="hidden" />`, not `<select>`