C# Retrieving large datatable from mysql takes too long (200k - 20 column records)

Im trying to get some data from datatable this is my code

          public DataTable getAllProducts()
    {
        MySqlConnection conSQL = new MySqlConnection(connectionString);
        conSQL.Open();
        MySqlCommand getProductsCMD = new MySqlCommand(@"SELECT
                                                  products.*
                                                FROM products", conSQL);
        MySqlDataAdapter adapter = new MySqlDataAdapter(getProductsCMD);
        DataSet productDataSet = new DataSet();
        adapter.Fill(productDataSet, "Products");
        conSQL.Close();
        if (productDataSet.Tables[0].Rows.Count > 0)
        {
            return productDataSet.Tables[0];
        }
        return null;
    }

Filling the datatable takes almost 10 seconds and takes at least 800mb of my memory. afterward i dump it to a class which is much lighter and my application will drop to 70mb. the problem is that 10 seconds (at least) . it takes too long. is there any way to make it faster?

Update:

to those who say call your data partially . i have tried that mysql bottlenecks the process. there is another list that we get from wholesale 200k . and it needs to be scanned and then check if we have that product in our database. 200k times asking from mysql only for one datarow for the program to scan it and do its procedure took about 40 min but if i load all the datatable in program and filter it in my own program it takes about 5 minutes to finish the whole work. so mysql is a bottleneck in this case.