public async Task <ICollection <JobOffer> > getAllOffersAsync(string specification) { var offers = await _repository.FindAllAsync(); foreach (var o in offers) { try { if (o.Field == specification) { theseAllOffers.Append(o); } } catch (Exception e) { e.ToString(); } theseAllOffers.OrderBy(j => j.PostingDate); } return(theseAllOffers); }