Very slow joined Queries

var q1 = Filter.Number.Select(item => new
                {
                    NH = item.Substring(0, 11),
                    NVH = item.Substring(14, 2),
                    NS = item.Substring(19, 11),
                    NVS = item.Substring(33),
                }).AsQueryable();

ret1 = (from v in VE
        where q1.Select(q=> q.NH).Contains(v.NH) &&
              q1.Select(q => q.NVH).Contains(v.NVH) &&
              q1.Select(q => q.NS).Contains(v.NS) &&
              q1.Select(q => q.NVS).Contains(v.NVS) 
        join deal in VDA
            on v.NIV equals deal.NIV
        where deal.time >= Filter.From && deal.time <= Filter.To &&
        deal.ModelCode == mdlCode
        let ccc = CT.FirstOrDefault(c => c.Ticket == v.SMF || c.Ticket == deal.SM)
        join list in LM on ccc.Mar equals list.MarE
        select new ReportData
                {
                    NIV = v.NIV,
                    AC = v.AC,
                    ID = v.NH + " - " + v.NVH + " - " + v.NS + " - " + v.NVS,
                    Date = deal.time,
                    UserId = ccc.UserId,
                    MAR = list.Name,
                    XX = ccc.x
                }).AsQueryable();
ret = ret1.Where(nr =>
    Filter.Mar == null || !Filter.Mar.Any() || Filter.Mar.Contains(nr.Mar)
).ToList();