The Eureka Surfacemax performed very poorly in our review and receives consistently bad ratings from consumers. In addition to your problem of blowing dirt everywhere, consumers complain about low performance, excessive clogging, leakage, bad belts, and other problems. You can read our full Surfacemax review and those of other Surfacemax owners here.
While it is possible that your vacuum may just have a clog, the more likely culprit is the vacuum itself. Your best bet is to buy a better vacuum cleaner. If you are on a budget, I would recommend looking at the Bissell Cleanview. If you can afford just a little bit more, then I would suggest one of the Shark vacuums such as the Shark Navigator or the Shark Navigator Lift Away.
If you can afford to sneak into the $200 - $250 range, then the LG LUV300B would be an excellent choice.