are there any supernatural manga like mushishi? maybe with nature themes or smth??

There's only manga that gives me a Mushishi type feeling & that is -
http://www.mangago.me/read-manga/natsume_yuujinchou/
But if you want to read something with nature themes then try this one -
http://www.mangago.me/read-manga/little_forest/

Look here. :)
http://myanimelist.net/manga/418/Mushishi/userrecs

thank you!!!!

gracias!!!!

Yes, Natsume Yuujinchou! There's even an anime with 4 seasons!