diff --git a/containment.cpp b/containment.cpp
index 37d9388c4..573a9741d 100644
--- a/containment.cpp
+++ b/containment.cpp
@@ -1101,7 +1101,7 @@ KPluginInfo::List Containment::listContainmentsOfType(const QString &type,
     QString constraint;
 
     if (parentApp.isEmpty()) {
-        constraint.append("not exist [X-KDE-ParentApp]");
+        constraint.append("(not exist [X-KDE-ParentApp] or [X-KDE-ParentApp] == '')");
     } else {
         constraint.append("[X-KDE-ParentApp] == '").append(parentApp).append("'");
     }
diff --git a/dataenginemanager.cpp b/dataenginemanager.cpp
index 126285e3e..810e3ea54 100644
--- a/dataenginemanager.cpp
+++ b/dataenginemanager.cpp
@@ -174,7 +174,7 @@ QStringList DataEngineManager::listAllEngines(const QString &parentApp)
     QString constraint;
 
     if (parentApp.isEmpty()) {
-        constraint.append("not exist [X-KDE-ParentApp]");
+        constraint.append("(not exist [X-KDE-ParentApp] or [X-KDE-ParentApp] == '')");
     } else {
         constraint.append("[X-KDE-ParentApp] == '").append(parentApp).append("'");
     }