title: Split series and replace with `\t` in Pandas
body: <p>My data type is <code>pandas.core.series.Series</code>. There are two columns. I want to split one of them from </p>
  
  <pre><code>V1      V2
  1000    1 2 3 
  1001    0 2
  </code></pre>
  
  <p>to </p>
  
  <pre><code>1000 \t 1 \t 2 \t 3
  1001 \t 0 \t 2
  </code></pre>
  
  <p>What I tried:</p>
  
  <pre><code>1.
  list(result.columns.values)
  result[list(result.columns.values)].str.split('  ').replace('/t')
  
  2.
  result['labels'].split('  ', expand=True)
  
  3.
  c = str(result['labels'])
  c.split(' ')
  </code></pre>
  
  <p>I have tried other methods, like use <code>awk</code> or regular expression. Unfortunately, I cannot believe I did not find a answer on the doc or stackoverflow.</p>
  
  <p>NOTE: the number of variables increases!</p>