Hi, I know game compnay will produce a Game Desing Document and User Manual during the game producing. Beside this, any more documents will be produced? What content will be included in the document?

A design doc, a source doc (all the files that will be in the game, picture files w/descriptions, text) Manual, Tech Support Docs - for the tech people if you have any - Troubleshoot Docs, usually. For like a strategy game, you might be adding a reference book (really tiny manual with all the stats) etc.

Hope it helps.