GOT IT !
If I run following query, it's all fine ...
select ccc_id, town, '*' + rtrim(TOWN) + '*',
'*' + replace(rtrim(town), char(0), '') + '*'
from CLI_CONTACT_CHANGES
where FK_CLIENT_CONTACLC_ID = '244_CORRESP'
Thanks a lot Luis for your help!!! Problem quiclkly solved 🙂