Relinth Thares
Hello, goodbye, thanks, goodbye, good-lord... you know a few of those.
Well the problem is there are different levels of words, depending on formality.
As for hello, in the morning you use ohayo if you want to be informal. If you're talking to someone who deserves more respect, use ohayo gozaimasu. For the after noon use konnichiwa and for the even use konbanwa, regardless of the formality level.
For good bye, sayonara is used if you won't see that person for a while. If you're going to see that person later that same day you want to use ja, mata. To be more formal you'll want to say ja, mata followed by shitsure shimasu.
If you want to thank someone informally, use arigato. To be formal you can either use either domo, arigato gozaimasu, or domo arigato gozaimasu
the good-lord thing can vary. If you're just meeting a stranger or someone who's not higher or lower than you, then you use the san- suffix. If you're referring to someone higher than you (like a teacher) or after a customer's name and such, you want to use the -sama suffix, which is more or less the same meaning as -san only more respectful. Also note that people in japanese more often refer to last names than given names. So in your case it would probably be Himura-san rather than Tyrsais-san.... Than doesn't do that because he doesn't know your last name.