Generally speaking, you can't. You can open them again from email, and (for apps which support this) you can save them after opening - for example, a text file that you open in Word can be saved to the Office hub - but the actual temp folder used for downloads is not accessible to anything except the app that does the downloading.
Do not private message me with questions that should have been posted on the forum! Not only are you wasting your time - I'm not going to bother writing an answer to such a question for only one person - but I will probably block you from PMing me in the future as well.
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