Hi Sofiane,
There will be a limit to the amount of support we will be able to provide. ICA-AtoM 1.3.2 is a very old release (2015) that is no longer supported, and we also do not test or develop with solutions such as WAMP.
There have been many improvements in later versions of AtoM, including important security patches, scalability and performance improvements, new features, and yes, improvements to the search index and how it handles multilingual content. If at all possible, I would strongly recommend that you consider upgrading to the latest version of AtoM, v2.6.4. See:
That said: have you added Arabic as a language under Admin > Settings > i18n languages, and then reindexed your site? This may help resolve the issues you are experiencing. See:
Good luck!
Cheers,