While you are considering sea currents...also add in winds that would scatter debris as well. As the break up (if that is what happened) occurred at a fairly high altitude then the lighter bits would drift much farther downwind than the more dense pieces. If there were thunderstorms about and strong vertical movement was involved it gets even far more complex to plot the dispersal pattern(s).
Add into this equation....the same effect as the wreckage settles to the sea bottom....and the debris field(s) that will generate. As the water is pushing 20,000 feet deep in that area....this is going to be a very difficult recovery operation and probably will not amount to much in percentage of wreckage being recovered.
Google a bit and read up on the research it took to discover the missing H-bombs from the B-52/KC-135 collision off the Spanish Coast many years ago.