Exposé doesn't expose all windows within a desktop

In Lion, I've assigned two apps, Word and Preview, to Desktop 3. So let's say I have a couple of Word docs open, and 1 Preview doc (a .pdf). When I'm working on Word doc #1, and I hit Exposé, it only shows all the Word docs open in that desktop -- ignoring the Preview doc also open in that desktop.

If I'm reading the .pdf, and I hit Exposé, I only see that one .pdf from Preview, and none of the Word docs sharing that space.

In Snow Leopard, if you hit Exposé, it would show all windows in a given Space -- even if you had windows from different apps sharing that Space. In Lion, is this function still possible?

Expose only shows windows of an application (in Lion), mission control will show you both preview and Word in your example