SoldItemsOnly not working

[LeighBicknell]

        $soldItemFilter = new ItemFilter();
        $soldItemFilter->name = 'SoldItemsOnly';
        $soldItemFilter->value = ['true'];
        $request->itemFilter[] = $soldItemFilter;

        $response = $service->findItemsAdvanced($request);

This always returns zero results. I've also tried various others, '1' does not work. '0' returns unsold items as expected.

Is there something i'm doing wrong, or is this an issue in the code?

[LeighBicknell]

After lots of playing around, I've got this to work. For those having the same problem, you must use the FindCompletedItemsRequest for this to work.