1-export module translation that you want to retranslate it or to overwrite on standard translation 

2- overwrite on  translation file 

3- you can follow any one of the following procedure

   A-activate debug mode >setting>technical>language > import/export

      and import the new translated file 

  B- create custom module with any  name but translated file inside folder by name "i18n_extra" --->inside __manifest__.py file add your module name that you want to retranslate it in depends---> add your  custom module to custom addon bath ---> restart odoo service --> update apps--> install custom module