This is exactly how it is used. As I pointed out earlier, the Coanda effect is used by many Ekranoplans and marine WIGs. By placing the engines/props ahead of and above the lift wings, a lift force is generated at low speed/high thrust. This lift force decreases the displacement of the in-water hull, reducing drag and wetted surface to the point that sufficient forward velocity can be picked up to get the lift wing working in ram/ground effect.
Jehardiman, again, you're not talking about the coanda effect. The coanda effect only appears when a jet travels over a curved surface and generates lift. This is not the case in the aircraft/wig-craft you show.
Let me demonstrate you the difference. The only aircraft that is using coanda is the An-72:
Jets are placed right above the curved surface of the wings.