Hello Narmina

Thanks for posting in the Community.

I'm sorry for not being able to reply in Russian and hope that I can assist in English. 

Could you double check that you're in the correct account? Sometimes users will use single sign on while signed into a different email account which can produce errors. I suggest that you make sure you've checked any and all Lucid accounts that might be under your email address(es).

Could you please check that the documents aren’t in your trash? If the document is in the trash check out this other Community post to know more about how to restore it. 

If the document you are looking for was shared with you and now you no longer see them in your account it is possible that whoever shared it with you rescinded your access. We would recommend reaching out to whoever owns the document to have them re-share it with you.

Lastly your document might be hiding in your browser history. If you carefully look through your browser history when you last worked on the document you might be able to find it. If you are able to find it please submit a support request here explaining the issue you are encountering and providing the URL of the document.

That should help our Support Team to track it down for you!