Lost data when the game crash

On multiple sessions that I played, Minecraft rarely crashed and no major data was lost outside of changing my current position to another not far away from the original.

The point is that I was playing my singleplayer Survival world for like 2 hours when Minecraft suddenly crashed (there wasn't any performance or world lag and the saving icon was constantly appearing that time), but it not only crashed, it erased a lot of the important progress that I made (items, xp, changes that I made to my world, etc.)
Seriously this bug needs to be fixed because I don't want to have another bad moment again :/