Can't figure out how to pop out your roller brush? DIYers often clean their vacuum heads with bent wire hangers or $2 plastic drain augers. Follow the route of your suction hose (if you have one) into the cleaner head.
Use the auger or hanger to root around near the area where that hose meets the head, and...ta-da! Paper wads and other offending cloggers are gone, without a visit to a repair shop.
Still losing suction after you've cleaned your filter? Your vac may have a second filter, and it may also be choked with hair or dust. (Our guess is that this guy's vacuum is actually clogged with shark teeth and the smell of fear.)
Sometimes your vacuum isn't broken. It's just the wrong appliance for the job. Some vacuum repair experts insist, for example, that uprights, such as this one from Panasonic, do a better job on thick carpets than other constructs.