How to filter datatable

Question

Helle sir/madam

i want to filter datatable. for that i am using  linq in this way its not working its give an error " The source contains no DataRows."

first i get a value in a datatable dt.

now i am using Linq

 var query = from r in dt.AsEnumerable()

                                            where r.Field<string>("AI_No_Of_Conception") == ""

                                                            select r;

 DataTable   dtLink=new DataTable();

                            dtLink = query.CopyToDataTable();

if any another option how to apply a query on datatable and bind it another Datatable then please suggest my.