Data Controls :: Fetching Values Of Same Field From Database In Different TextBox

I have one page on which there are 6 labels and six text box for subject apart from this there are 2 to 3 other text box and label for studnt information. i want to do in such a way that if i enter student enroll no i get his/her name ,dept,sem,all subjects on 6 labels and marks related to subject in text box. In table there are fields 

Marks_Entry
Student_Enroll Student_Name  Sem   Program           subject                                   Marks 

1                         sss                   1         BCA      Basic Communication Skills                75
1                         sss                   1         BCA      Mathematical Foundation                   85

[code]...

now when i am entering roll no in form then student name ,program, sem is fetched but in label 1 to label 6 same subject name that is 1st subject name is copied and in text box also first marks are fetched in all textboxes..my c# code on student enroll textbox is this

protected void txtEnroll_TextChanged1(object sender, EventArgs e) {
conn.Open();
qry = "SELECT * FROM Marks_Entry WHERE Student_Enroll_No = '" + txtEnroll.Text + "'";

SqlCommand cmd = new SqlCommand(qry, conn);
SqlDataReader dr = cmd.ExecuteReader();

[code]...

how can i get different values from database