There are currently two search engines implemented. The one you use
when you start typing in the search box in the upper right corner is
currently based on a MySQL prefix search. We are actually working on
changing this, but this will take time.
When you are using Special:Search you are using an other search
algorithm that, I believe, supports what you want. You can try this on
: Typing "Comite" in the upper right will not find
"Comité", but Special:Search will.
You may need to install
to have this
feature in your installation.