Here's some more grammar points on -던데. -던데 definition: 1. seeing that ..., given that ... It makes a dependent clause recalling one's past experience to support what one is going to say in the main clause. 2. I saw that ... (so what do you think? / what do you say to that?). It's a sentence ending form recounting one's experience to invite a response from the listener, like "what do you think?". Examples: 1. 집앞에 차가 많이 와 있던데 무슨 일(이) 있어?: Is something the matter, as I see all these cars in front of your house? 2. 그 친구 큰 집으로 이사했던데!: You know what, I saw that he has moved into a big house! You interpreted that line correctly. - 와우!!감사해요~~ 딴것도 있던데,,ㅎㅎㅎ 물어봐야겠네용ㅎㅎㅎ => Wow, thank you. I saw some other items too ... I'll ask (them) about those, haha. The syllable 더 is usually associated with some sort of past experience when used in a verb or sentence ending. There are a few different usages and variations but they all have this underlying meaning. - 그 친구 이번에 보니까 취직했더군. I saw him recently. He has a new job now. * -더라, --던데, -더군, -더구나 all have similar sense and can be substituted here. * -던데 can be thought of as -더라 combined with -ㄴ데 ending which leaves the sentence open ended for effect. - 내가 살던 집. The house where I used to live. - 내가 과거에 했던 일. The work I used to do before. * -아/어던, -았/었던 make a past tense adjective form from a verb, like "(something) that I used to do".

~던데 is use for something you experienced yourself. Not that everytime we talk about something we experienced we should use ~던데. But when it is used, it is for that nuance. 딴것도 있던데 ! There's another gift too ! (I found that there's another gift too !)