Confusion about History

Confusion about History

Can someone explain to me how saving when collaborating with more than one other individual works in Zoho? We feel like the document is not saving our edits when in "share mode", but maybe we don't understand the process.
 
Some more information: The file will erase the most recently updated information (even after it is saved) once another member logs on to edit. Then, sometimes the save button no longer produces a new version. These are just two examples of the "errors" that have happened when we attempt to collaborate on a project. I believe all the members are using the recommended internet browsers, so what's going on? We are a research team working on an article and we are TIRED of losing our work. 
 
 
 
Please help.