public async Task <IEnumerable <Loan> > GetLoansOfUserAsync(int userId) { var spec = new Specification <Loan>(x => x.LoanUsers.FirstOrDefault(y => y.UserId == userId) != null); spec.Includes.Add(x => x.LoanUsers); IEnumerable <Loan> loans = await _loanRepo.FindAllAsync(spec); return(loans); }