1 Shoganai is an important word in Japanese. It can be translated "it can't be helped." It's often used to describe Japanese culture, thinking and values. Shoganai is essentially a philosophy. It says that if something is out of your control it's better to quickly accept it and move on  しょうがない

2. Naruhodo - I see, (in the I understand way or i see your point) - なるほど

3. “Soka” or “Sokka” are generally colloquial pronunciations of “Sou ka”, or more politely “Sou desu ka”. It generally means something like “oh, is that so?” but in certain contexts can be kind of like “Oh I see.”  そう か 

4. yappari   something like "as I thought" and shows that the speaker had a preexisting suspicion that a certain matter was indeed true  やっぱり