Solution : https://service.sap.com/sap/support/notes/45463 (SAP Service marketplace login required)
Key words : 
set                    sap_codepage                    saptemu/codepage                    install/codepage/appl_server                    install/codepage/db/non_transp                    install/codepage/db/transp, install/codepage/db/non_transp  =8600            install/codepage/db/transp      =8600            abap/import_char_conversion     =0            zcsa/installed_languages        =e2, install/codepage/appl_server    =8600            zcsa/system_language            =2, database~~~~~~~~     sap installes standard english database, change required        thai windows 95        slanguage=thi, frequently asked basis technological questions, zcsa/installed_languages       =e2, import codepage correction transporta30k003804, abap/4 thai sorting language element, thai country version cdrom 31h
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