keyword searching result from database in C#

public static DataSet RelatedKeyword(string keyword)

{string[] arr =keyword.Replace("& ","").Split(' ');

DataSet ds = new DataSet();

DataSet dsTemp = new DataSet();

bool flag = false;

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["remote"].ConnectionString);

// DBAccess db = new DBAccess();

SqlDataAdapter sda;

foreach (string s in arr)

{ if (s.Length >= 2)

{ sda = new SqlDataAdapter("select distinct top 60 keywordid, keywordname from keyword  where keywordname like '%'+@ksearch+'%'", con);

sda.SelectCommand.Parameters.Add("@ksearch", SqlDbType.VarChar).Value = s;

sda.Fill(dsTemp);

sda.SelectCommand.Parameters.Clear();

ds.Merge(dsTemp);

if (flag == false)

{DataColumn[] pk = new DataColumn[1];

pk[0] = ds.Tables[0].Columns["keywordid"];

ds.Tables[0].PrimaryKey = pk;

flag = true;

}}}

return ds;}