SharePoint offers exceptionally good search functionality, making it easy to find the documents you need. However, a great search tool needs good data, and that part comes down to you. To ensure you can always find a document, make sure you develop a consistent and easily understandable naming structure for the documents within your libraries.
Don’t get lazy (we’re all guilty of doing so). Each new document you create within SharePoint is automatically named “document.” Before creating the body of the document, give it a name and ensure that the title makes it clear what the document is about.