「私にも教えてよ！」
「てゐに聞いてみたんだけど、
　楽しいことって以外何も教えてくれなかったの。
　私にも教えてよ、ひとりあそび！」

IB4T, Google Translate still is confusing and gives little options to translate, but I get the gist that she's curious on what the "fun" is about "playing alone" cause no one is telling her.

Su-san seems to know perfectly well...

"Tell me too!"
"I asked Tewi, but she wouldn't tell me anything aside from that it's fun. Tell me about playing with yourself too!"