I got rejected 4 times and waiting for 5th time.my images are approved at SS and all other major stock sites,but istock seems to be very hard for new photographers.

i also got rejected 3 times in illustrations section as well,but got approved 2 illustrations  in last 2 submission and waiting to submit last one.

i dont think so i am old enough in this industry to give you any big idea apart this that you keep trying but one thing i learned from all that rejections that new photographers need to come up with something really grt to get in.so think unique.

Best of luck

In the first image, I find the perspective lines problematic.  The lines of the doorway on the right feel awkward, as does the wall on the left.  I'd consider stretching the top left and top right to make the whole thing more perpendicular.  I also notice that the brick walk isn't straight; it moves up from left to right.  Also, you cut the corner of the leftmost plant, so the leaf seems to enter the scene from nowhere.

In the second, the lower row of lanterns is cut off at the middle.  Given all the empty (and dull gray) sky above, why not reposition lower down to show less sky and more lanterns?

The blown out sky in the third is distracting, and so is that little bit of building in the upper right.  At minimum I'd edit that out.  Better would be to change viewpoint a little to the right to lose that bit of building and the leftmost lantern you cut off.  Best would be to reshoot on a day when the sky isn't so dull.