The use of a class here is not worth the effort here. 
Just declare a new object `Search.FuzzySearch = {}` and extend it. For example: 
````javascript
Search.FuzzySearch = {};

Search.FuzzySearch.find = function()
{
    //...
};

Search.FuzzySearch.findByPath = function()
{
    // ...
};
````

In case you need to declare functions you don't want to expose (aka helpers), you can add them at the end, like there:
https://github.com/fflorent/firebug/blob/1135b815f1d1f2c8f89d7739557058963f72eb8e/extension/content/firebug/html/layout.js#L539

And you can also declare private variables/constants at the beginning of the file, like there:
https://github.com/fflorent/firebug/blob/1135b815f1d1f2c8f89d7739557058963f72eb8e/extension/content/firebug/console/consoleInjector.js#L19

Florent