Load txt on Android from StreamAssets folder

Hello, I´ve been trying to load an txt document, I tried differents ways, but none works(I found some post, but almost all were from two or more years ago). The Idea is to have different txt files with the dialogues in differents languages, to change the texts dynamically.
I readed lot of posts but none have a real solution to this, or I didn't understand it. (by the way sorry for my english, I´m not native speaker)

The things that I already know:
-apk file is like a zip file and is necessary to use WWW class to read it(Unity documentation)

Things I need to know:
-Which path to use? Application.streamingAssetsPath, Application.persistentDataPath, Application.dataPath. The Unity document say that is necessary to use DataPath on android Devices and WWW class to open it.

​

-Is the "!" symbol on the path necessary?, and what is his function?(I know it in coding("negation operator" !), but not in a path)

Note: I´m testing in a new apk file, to prevent ruin the real app code

This is the base code I have been using, I changed it a lot of times, but didnt work :

Code (CSharp):

1.  
2.    string textoPagina = "";
3.  
4.     void Start () {
5.            StartCoroutine(read());
6.     }
7.  
8.     IEnumerator read() {  
9.         string rpath = Path.Combine(Application.streamingAssetsPath, "test");
10.         //string path = "jar:file://" + Application.dataPath + "/txt/test.txt";
11.        
12.         WWW www = new WWW(rpath);
13.         yield return www;
14.              
15.         StringReader streamReader = new StringReader(www.text);
16.         textoPagina = streamReader.ReadToEnd();
17.         Text texto = GetComponentInChildren<Text>();
18.         texto.text = textoPagina;
19.        
20.     }
21.  

"texto" is the button text that I want to change the text dinamically to test it.
I have two documents "test" one in a txt folder, and other one on StreamingAssets folder, both have different frases to know which one was loaded

 

It's really easy to read a txt file that you've added to the project as a resource:

Take a look here: http://forum.unity3d.com/threads/file-input-best-practices.336965/#post-2180389

And a bit more info here: http://forum.unity3d.com/threads/storing-a-my-data-file-into-ios.326974/

 

Thanks, is working at the momment,