Search by using EntityFramework
===

Am trying to search the student details with their name or email or mobile. For this I've three textboxes for Name, Email and Mobile.

And in my code I tried to get these details like,

    DataObject entities=new DataObject();

    foreach (DataObject.Student student in entities.students.Where(p => 
              (p.FIRSTNAME+p.LASTNAME).Contains(txtName.Text)
              || p.MOBILE.Contains(txtMobile.Text)
              || p.EMAIL.Contains(txtEmail.Text))
            {
                //
            }

and here, if I type `sham` in the Email or in the Name textbox, its listing all the student details available in the database instead of listing only the student name or email contains `sham`.

When I was debugging this, I tried giving the same value`sham,sham,sham` for name,mobile and email its listing perfectly, and also if I want to search by name that contains `sham`, and If I type `sham` in name, and anything else in the email and mobile, this also working perfectly....

One thing I came to know from this is, it expects all the parameter should have some value, I dunno why this expects like this, and I dunno how to fix this, can anyone help me here. Thanks in advance