YOU SAID:
how do i say this thingy that i don't know?
INTO JAPANESE
わからないことをどうやって言うの?
BACK INTO ENGLISH
How do you say something you don't understand?
INTO JAPANESE
理解できないことをどのように言いますか?
BACK INTO ENGLISH
How do you say something you don't understand?
That didn't even make that much sense in English.