Vornne:
Other quests work the same way. After you say something to an NPC, it is passed through some steps to translate what you said in something more standard. Synonyms are translated to a single form. For example, "hi", "hello","goodmorning" all translate into "greeting", so that if "greeting" is a trigger, you can say all those things. Somewhere, also some words are removed that are not needed (I think). So if you say "Can I bring you something?", this translates into "can bring you".