Also to go along with what Brenden has mentioned, are you trying to show only English items in the drop down for the English culture site and only show Arabic items in the drop down for the Aracbic culture?
Firstly, we're assuming you're using Kentico Cultures
If this is the case, are you selecting the correct culture in the pages application/section for the 'Type' field?
Secondly, if the assumption is correct, can you provide us with some examples of the values your storing in the Localisation section as Resource Strings please?