Hi buddy,
No, there is no stronger fan. The preinstalled fan is enough for preinstalled hardware and pretested by Toshiba. You don’t need another model.
An exact cleaning description you can find here:
http://forums.computers.toshiba-europe.com/forums/ann.jspa?annID=40
Furthermore it’s important that you use the original Toshiba display driver. Other 3rd party display drivers can also cause overheating so I would recommend installing the newest display driver from Toshiba page.
Don’t forget that the notebook should be placed on a clean disk with enough free space around it. Don’t put the notebook on your bed or tablecloth.