You can combine all you want but your only going to be able to detect the strongest wood.
Most pitmasters will use 1 wood for heat (oak) and add another for the actual flavor.
I burn 100% Shagbark Hickory.
If i were to add any other wood to that you would never know it was in there. (except maybe Mesquite)
If your using chunks stick with 1 flavor but change it up every smoke until you find what you like.
Pitboss @ Woodpile BBQ Shack
I cook the best brisket north of Dallas. Get over it.
Michigan State Lead-Operation BBQ Relief
BBQ Person of the Year 2013