Side by side, yes. Back to back, no.
If two magnets have a pull of 2 lbs ea., then two of them side by side can lift 4 lbs, since they act independently, just like suction cups.
One magnet behind another will not multiply attractive force proportionately. If this were true then longer magnets would be proportionately more powerful than shorter ones, which is not the case.
And remember that magnetic sheets are not really true magnets like solid ones, with a north and south pole. They have been magnetized in spots on the surface with alternating N and S areas.
Don
Kansas City