Documents disappearing on my MacBook Pro even after saving them

While I was writing in a document for days, I am pretty much sure that every time I was saving the changes. but suddenly I could not find the document at all it looks like the document is shift deleted.

this is not the only time I experience such thing happens.

also one time I found all my folders were empty with out deleting the items in it.

This is a shame bug in Apple Product and needs to be resolved immediately.

[Re-Titled by Moderator]