They're probably from the same epicenter. U might have the quake's center 100 miles underneath italy. whats gonna happen is that the wave starts to propagate in different directions as it encouters different materials which conduct the wave faster or slower, and which will refract the wave causing it to move in a slightly different angle. as such u can have an earthquake in italy, and another 3 in pakistan, from the same center, with varying intensities. Heck, u could have an earthquake in italy and another one on the exact opposite point on the other side of the globe. think about sunlight and a prism. it refracts the light so u see all different colors which move in different directions after hitting the prism, and at different speeds, with different intensities. if u had 2 prisms put together, so that after hitting the first the different waves of color, already moving in slightly different angles, now hit the second prism, their directions will be starkly different. Add to trhat the fact that there''' be some reflection off the prism in the opposite direction, as well refraction, and u could have a number of seismic activity in different points of the globe from the exact same center.