Cómo obtener los archivos solo por nombre de archivo de Sharepoint

Currently I am getting the list of documents as following:

 private ClientContext _clientContext;
 var oList = _clientContext.Web.Lists.GetByTitle(SERVERURL);
 var oQuery = new CamlQuery();
 var fileList = oList.GetItems(oQuery);
_clientContext.Load(fileList);
_clientContext.ExecuteQuery();

It gives me all the files that is on the server.

But what if I know the files that I want to open from SharePoint and Read? I don't want to load all the files and then loop through them , instead want to get that particular file from SharePoint.