Hmm........yeah, that is weird. Not sure what's going on there.
Did you set the date parameter to 'Any date' rather than leave the default on (A year ago)? That will defo. make a difference. There won't be any returns for less than a yr old - the forum has now been inactive for a lot longer than that. Worth a try if only to eliminate it as a possible explanation.
If still no joy, can you tell me where you're based geographically? Country name will do. I can then make enquries about possible geographical restrictions, but I think that's an unlikely explanation.
I've made enquiries about the book, so I'll let you know as soon as I get a reply.