on the expertflyer.com homepage - before you log in - there is a link on the left where you can download a PDF of all codes for reward tickets that are viewable. Note that United does not show this information on expert flyer- but you can search on united.com using the book award travel option. Also, from the looks of the PDF, Lufthansa does not show award availability on Expert Flyer either.

One last thing, note that for AC, you have to specify the booking class you're looking for in your search of it will not come up for reward tickets.

Hope this helps.