A couple lebih Tumblr questions...

I'm slowly getting the hang of it I think but I have two lebih questions:

1. When I cari all of tumblr (not just one blog) for something like a tv tampil for example, is there a way to cari tumblr based on upload tanggal like on youtube so it'll start with the very first posts about that topic and go from there instead of the most baru saja ones?

2. Can I post a komentar on someone's post without reblogging it atau do I have to reblog it and if I reblog it just to post my komentar and then hapus it from my blog will others still be able to see my comment?

Thank anda for your answers! :)