"reduce the suction power"
The Electrolux Mo L from the 60s & 70s was,and still is, a great vac.As above it uses same type C bag that most Elux have used until the type R was added.A good generic multi layer bag will work well and might be found at some grocery/dept stores.The reduced suction might be from a good vac with a bad hose.To find out-remove hose,put in clean bag,turn on,feel suction at vac,replace hose,feel suction at end of hose.If less you may have a clog(drop marble through to find out) or a hose leaking air.Again easy to fix/replace at vac stores or internet.