Retrieving unique values from List

Hi,

I am working on Sitefinty 9.1 . I have created a list content type in Sitefinity. I need to fetch those values from the list. I have done like this:

List dropDownItems = listManager.GetLists().Where(l => l.Title == "OurProductsChild").FirstOrDefault();

I am getting the values, but it is duplicated. ie one for english and one in invariant.  I wanted either english/invariant one. Can anyone tell how to approach this. Thanks