I am creating a SharePoint Document Management site on modern sharePoint online environment for multiple department. As my main focus will be people can search the document with minimum effort with the help of search box and search refinement also we want to avoid 5000 limit issue.
Any recommendation and best practice to design good DMS system.
You dont have a 5000 limit issue if its a modern sharepoint site.
SharePoint Search is quite powerful in SharePoint Online which can display your search results
If you have any custom rules individual to your department,create each site for each department so that you can have better control over the user permissions by department and you can define custom rules.
Otherwise,you can create one site with multiple document libraries by each department
or One document library with multiple department folders underneath it.