2017中非去产能合作展:为什么我的查询后没有结果啊?

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
If Request.QueryString("para") = "back" Then
Dim myconn As New OleDb.OleDbConnection
Dim myds As New DataSet
myconn.ConnectionString = "provider=microsoft.jet.oledb.4.0;Data Source=" & Server.MapPath("test.mdb")
myconn.Open()
Dim sqlstr
sqlstr = "select * from problem where title like '%" & Session("txtcxnr") & "%'"
Dim myadpt As OleDb.OleDbDataAdapter = New OleDb.OleDbDataAdapter(sqlstr, myconn)
myadpt.Fill(myds, "table1")
datagrid1.datasource = myds.Tables("table1").DefaultView
datagrid1.databind()
myconn.Close()
Session("txtcxnr") = ""
End If
End Sub

Private Sub btncx_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btncx.Click
Dim myconn As New OleDb.OleDbConnection
Dim myds As New DataSet
myconn.ConnectionString = "provider=microsoft.jet.oledb.4.0;Data Source=" & Server.MapPath("test.mdb")
myconn.Open()
Dim sqlstr
sqlstr = "select * from problem where title like '%" & txtcxnr.Text & "%'"
Dim myadpt As OleDb.OleDbDataAdapter = New OleDb.OleDbDataAdapter(sqlstr, myconn)
myadpt.Fill(myds, "table1")
datagrid1.datasource = myds.Tables("table1").DefaultView
datagrid1.databind()
myconn.Close()
Session("txtcxnr") = txtcxnr.Text
End Sub
Private Sub DataGrid1_DeleteCommand(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs) Handles DataGrid1.DeleteCommand
DataGrid1.EditItemIndex = -1
Dim myconn As New OleDb.OleDbConnection
Dim myds As New DataSet
Dim mycmd As New OleDb.OleDbCommand
myconn.ConnectionString = "provider=microsoft.jet.oledb.4.0;Data Source=" & Server.MapPath("test.mdb")
myconn.Open()
Dim sqlstr
sqlstr = "delete from problem where id=" & e.Item.Cells(2).Text
mycmd.Connection = myconn
mycmd.CommandText = sqlstr
mycmd.ExecuteNonQuery()
sqlstr = "select * from problem"

Dim myadpt As OleDb.OleDbDataAdapter = New OleDb.OleDbDataAdapter(sqlstr, myconn)
myadpt.Fill(myds, "table1")

DataGrid1.DataBind()
myconn.Close()
End Sub
查询的时候不出错,但是数据库里面有合适的选项和结果,但是就是查询不出来,不显示认识数据,请问这是为什么啊?