title: add new synonyms in elasticsearch
body: <p>I created the synonym file (synonym.txt) in my index and it is already working correctly when I search for words that have synonyms.</p>
  
  <p>However I have a question! If I need to add new synonyms in the file (synonym.txt), how do I make the new synonyms work? because when I add new synonyms it doesn't work, it only works the synonyms that already existed in the file (synonym.txt) when I created my index.</p>
  
  <p>Thanks</p>