in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\SearchPane set
"NewSearchPane" (DWORD) to 1
"NewFilesSearch" (DWORD) to 1
"NewSettingsSearch" (DWORD) to 1

and in HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\SearchUI set
"RestartView"(DWORD) to 0
"ConnectedSearchEnabledTestHook"(DWORD) to 1
restart explorer after this.