Generally, cracks that run parallel to the glass fibers are irrelevant. Note that I said generally. You can't tell for sure from a picture. One way to fix these cracks is to fill them with super glue. Put some glue in a shallow dish, stretch some thread out between two forceps or pliers (you don't want to use your fingers) and dip it in the glue. Then lay the thread on the crack and let the glue wick in. I've not tried this method yet as I've not had this problem, but you have nothing to lose. Do be careful drawing the bow for a while after repair. Eye protection is a good idea. I've fixed bows with lim lam cracks and lim delamination and always draw them carefully (listen to them) and with eye protection until I have put at least a couple hundred arrows through them.