title: How to locate matches in two dataframes with contains
body: <p>How caqn I locate a string from a dataframe field (df1), in a string from another dataframe field (df2)? Is it possible with the command contains?</p>
  <p>Example:</p>
  <pre><code>df1[field1]=&quot;CEG&quot;
  
  df2[field2]=&quot; CRAT Z.8.1 and Z.8.2 (INC-0022540490) M-137 --- NT[002][URB:1-CEG PET:GR.7:C2-98-S1] --- &quot;
  </code></pre>