1. The water when it was under ground, was adding bouncy to the land, when the water gushed out there was a vacuum.
How is that even possible for water of that magnitude to be underground? Land is heavier than water and that much water would have seeped through the land. It's simply not possible for all/most of the water in the world to have been underneath the land with the land floating on top of it. That's possible with ice, but not land. Sure there is underground water, but that water is of a much less magnitude and it all eventually goes back to the sea or is taken up to the surface by plants, animals, etc. And what do you mean land was "bouncy"? What, you could jump on the Earth and it would act like a trampoline? Again, physically impossible.
2. Or weak hollow spot, which was quickly crushed.
It's impossible for there to be a gigantic hollow spot inside the Earth, or any known kind of planet for that matter. How would this hollow spot be able to stand all the pressure of the weight of the land above it? When the Earth was being formed, how would a hollow spot be able to created when meteorites were crushing into the Earth with such force that the Moon was blasted off from Earth and into space?
3. Where is the land going?
It can go underneath the ocean if the sea level rises or it can slide underneath other land. It can also be created if the sea level drops or from volcanoes. When two plates cause land to slide underneath each other, that typically forms a volcano, and volcanoes create more land. It's a cycle.
4. I don't see it.
5. Still looking at the same land as far as I know.
Of course you don't see it. It's an extremely slow process, and unless you live in an area that is tectonically active, you really have no chance of seeing even subtle differences.
7. Many of *The Mammoths* died chomping on greens, food have you, where did they get it, if they were hip deep in snow?
Just because when we found them deep in snow doesn't mean that they were in snow when they died. Climate change changes just about every area of the Earth into something very different. Mammoth fossils are most commonly found in areas that were believed to be covered by grasslands and savannas, and their main diet supposedly consisted of grasses. They are also found in areas that are believed were formerly tundras. Exactly what they were doing up around tundras some of the time, I don't think anyone really knows. It is entirely possible that there was some slight vegetation there at the time, or they crossed tundras due to migration.
10. Show us where we are getting some new land, and don't show us some obscure place on the bottom of de sea.
Certainly; Hawaii is getting larger in area every year due to volcanic eruptions.

As you can see in this picture, fresh lava has extended out toward the ocean and touching the water, making the steam rise. Because of that, a small bit of land was just added to that coast of Hawaii.