I love Neroli sauvage too. I had a similar problem, however the reason your neroli sauvage doesnt last is because there are multiple "batches" of it due to the natural ingredients which vary by season. Some batches smell less citrusy, more dry and woody (and last for hours), while others smell more like neroli and last a maximum of an hour.
So.... you can either spend some time looking for a good bottle, OR (drumroll please) try Annick Goutal's Eau du Sud. To me, this is the closest I've come to finding something like neroli sauvage at its best. Although they smell different, I get the same great vibe from Eau du Sud.
At its worst, Neroli Sauvage smells just like neroli with some citrus. If this is the batch your looking for, I'm sorry but I don't have any suggestions