At the risk of adding to the confusion by having several different search blocks for MoodleDocs, I've created a simple one, which uses the Moodle search facility and not Google.
The code is basically the FORM code from the search block on the left-hand side of MoodleDocs itself, put inside a simple Block. It's a standalone file, it uses no language file or database table, and it opens the results in a new browser window.
To install it, create a folder called 'searchmoodledocs' in your 'blocks' folder and copy the attached file into it. Then go to your Moodle and click the 'Admin' link in your main 'Administration' panel. That should set it up, and you can then add it from your 'Blocks' dropdown.
As I said, it doesn't use a language file, but there are only three things you need to change for another language. These are the en in the Form's 'Action' statement, (which define which language section of MoodleDocs it will search) and the text on the two search buttons, which is defined by the button's 'Value' property.