Well i realized something with seeds, someimes the seed shell is too thick, or too hard, and some streams have problems with germination, cuz they cant absorb enough water.
This technique has gave me an amazing succesfull rate.
1st put the seeds in a water glass for 24 hrs, make it sink
2nd if it hast spread, take a very sharp blade, and cratch the sides of the seeds, (to make the sides of the seed thinner) do not scrath it too much or youll kill it, and when you do it do not press the seed too hard or you are gonna break it.
3rd put the seed again in water 24 hrs, it will at some moment of this crack, and show the tip of the root.
4th put it inside the soil, with this tip looking down, in the must vertical way as possible.

***Do not touch the root tip!!! do not try to help the seed opening it, youll kill it.
and if you got another question just post it, and be carefull dont do anything if you didnt understand me well...