TM search in SDL Studio 2011 returns different results as the API does.

Hi all,
Studio 2011 offers the ability to search for a term in a file-based TM. I would like to use the API in a utility that I am writing. However, when I enter my term in Studio, I get different results from my program. The program looks like this (it is very similar to the sample application that comes with the SDK).
SearchSettings settings = GetSearchSettings();
This results in the following settings-object:
 
SearchResults results = _fileTm.LanguageDirection.SearchText(settings, searchText);
Any idea what could be the cause? Your feedback is much appreciated!
Henk