You can try walking hills, pressure points, a cup of prune juice, spicy foods: I drank a glass of prune juice and was in labor within 12 hours...however everyone else is right if baby isn't ready then none of the natural remedies will change much of anything!! But we can always try!
You could try laying on your side with a large ball between your legs. I wasn't dilating in my last pregnancy (38w3d) and the nurses put a peanut ball between my knees. It's an exercise ball shapped like a peanut. I was in labor already but had been there nearly 24hrs with no dilation. The ball had me fully dilated in just a couple hours. Don't know if it'd help before labor but you could try.
Baby will come when baby is ready unfortunately no amount of natural labor induction remedies will change that. Sex, squats and walking are normally the safe go to's, walk daily if you are able I'm sure it's hard when your short of breath. You can also try swimming, and eating spicy food. Good luck you are almost there :)
Pregnancy is no easy job, but after several pregnancies- I have found that nothing will make you go into labor if your body and baby are not ready. It sounds like you are making some progress- that's pretty good for 37 weeks. There are many theories on things that can help (spicy food, the three items you tried, raspberry leaf tea, etc), but it's easier in the long run if you wait for it to happen in it's time. With my second, I tried everything I could think of- nothing worked. I was at a 5 for weeks and weeks- she was my only late baby, lol. After that experience, I decided to just wait it out- labor and delivery was much easier when I went with the flow.
Good luck and I hope you will be holding your little one soon!