Can a human be blown away by jet engines of an A380?
Absolutely. The jet engines used in airliners are quite powerful and can easily blow away human beings, vehicles and small aircraft. Other (large) airliners, not so much.
It depends on the aircraft's size, weight and distance from the engine actually. There are records of a F-16 being tipped over by a B-1B Lancer; as the thrust of an A380 engine is quite higher than that of the Lancer, the damage would be worse.
The minimum safe distance between the aircraft varies depending on the aircraft and engine type. For example, according to the Australian Civil Aviation Order 20.9 - Air service operations - Precautions in refuelling, engine and ground radar operations:

An aircraft engine shall not be started or operated:
...
(b)   within 8 metres (25 ft) of other aircraft;
... turbine engines, in addition, shall not be operated within the appropriate distance specified below of any other aircraft, fuelling equipment or exposed public areas which lie to the rear of and within a 15 degree arc either side of the exhaust outlet axis of that engine:


Minimum distance between aircraft for operation of engines; image from Civil Aviation Order 20.9 - Air service operations - Precautions in refuelling, engine and ground radar operations