SF_10.1, SF_10.2, SF_11.0, SF_11.1, SF_11.2, SF_12.0, SF_12.1, SF_12.2, SF_13.0, SF_13.1, SF_13.2, SF_13.3, SF_14.0, SF_14.1, SF_14.2, SF_14.3 - https://docs.sitefinity.com/for-developers-query-documents

QueryDocumentByMasterIdFluentAPI.cs

using System;
using Telerik.Sitefinity;
using Telerik.Sitefinity.Libraries.Model;

namespace SitefinityWebApp
{
    public class QueryDocumentByMasterIdFluentAPI
    {
        private Document GetDocumentFluentAPI(Guid masterDocumentId)
        {
            return App.WorkWith().Document(masterDocumentId).GetLive().Get();
        }
    }
}