Try:
string query = "select pcode,fundingagency from project where (pcode like '" + TextBox1.Text+ "') or (fundingagency like '" + TextBox1.Text + "')";
SqlDataAdapter adp = new SqlDataAdapter(query,con);
But seriously, you shouldn't do it like that at all! Do not concatenate strings to build a SQL command. It leaves you wide open to accidental or deliberate SQL Injection attack which can destroy your entire database. Use Parametrized queries instead:
string query = "select pcode,fundingagency from project where (pcode like @SS) or (fundingagency like @SS)";
SqlDataAdapter adp = new SqlDataAdapter(query,con);
adp.SelectCommand.Parameters.AddWithValue("@SS", TextBox1.Text);
Both of these assume that the user has added the '%' character to his text box.