Pick up the two dark blocks (big first then small) and the wooden plank. Drag the wooden stump to the right until it can't move anymore.
Place the wooden plank on the stump. Tap the left side of the plank to make the broken cart rise for a second. Quickly place the FIRST big block (should be 1st item slot) under the right side of the plank.
Tap the left side of plank again and place the other block on top of the other block.
Take the wooden wheel in the cart. Drag the oil can to right of cart into oil bucket and drag the oil can all over the cart. Once you let go of it, the oil can should disappear off the screen.
Now attach the wheel to the cart and tap around the cart to make it leave and open the door.
Proceed to the next level!