Rather than changing the Google Suggest entries, it might be a better strategy to change the search results that users see when searching for you company name.
I'm guessing at the moment there is something negative there that you want to remove (ie. Yourcompany name sucks)?
Depends on the situation as to what is the best strategy, whether it's misinformation on pages you can control or a bad review on another site for example.
Maybe provide more info and we can offer specific help?...