If you have a document in the trash can on your Mac, you can't look at it by just opening your trash can and click on the document. What I've always had to do is to pull the document out of the trash, open it, and then put it back into the trash when done. But there is an easier way to do this that doesn't require you to pull the document from the trash. Instead, you can pull the document out of the trash and just put it on the Dock icon of the application you want to open it in. For example, if you have a word document in the trash, you can just drag it to the Word icon on your dock and the document will open even though it is still in the trash.