مشكل در جستجو ي كريستال ريپورت

[gladiators1980]

دوستان مشكلم اينجاست كه اگه جستجو بر اساس هر دو فيلد چك باكسامو انجام بدم جواب درست نمي ده

if (checkBox1.Checked)
{

objDataAdapter.SelectCommand.CommandText = "SELECT er as Column1, tozih as Column2,fie as Column3, number as Column4,allfie as Column5,yearvo as Column6,monvo as Column7 FROM khadamat where monvo =" + "'" + textBox1.Text + "'" ;
}
if (checkBox2.Checked)
{

objDataAdapter.SelectCommand.CommandText = "SELECT er as Column1, tozih as Column2,fie as Column3, number as Column4,allfie as Column5,yearvo as Column6,monvo as Column7 FROM khadamat where yearvo =" + "'" + textBox2.Text + "'";
}

DataSet1 objDataSet = new DataSet1();
objConnetion.Close();

objDataAdapter.Fill(objDataSet, "DataTable1");


CrystalReport1 objRpt = new CrystalReport1();
objRpt.SetDataSource(objDataSet);

crystalReportViewer1.ReportSource = objRpt;
}