Something Japanese doesn’t notice

Hello,

We had again Osusowake from a French tenant. Lovely:) 
 

I actually have once eaten one of them before.
While I was talking with tenants, I unintentionally said「懐かしい(Natsukashi)なあ」.

We(Japanese) can understand the meaning of its word, but there is also something Japanese doesn’t notice. 
They told me this word is really really really useful word.

「What’s the meaning in English??」
We may express the meaning instead of these words 
・remind me of ~ 
・miss ~ 
・bring back memories 
・good old days 
Otherwise none of them express the meaning perfectly.
Maybe 懐かしい can express all the meaning all at once.

Japanese are knows as quite people and don’t talk a lot because of cultural roots.
So this word might have a lot of meaning not to need talking a lot.(It’s my guess)
We talk more seriously sometimes, exchange our opinions on topics 🙂