简单一点最好

My attempt, not romantic.

http://www.answers.com/fog?cat=biz-fin
in a fog 困惑的, 像在霧中的

Chinese汉语 term (edited): 里看花，谜境重重

a riddle wrapped in a mystery inside an enigma (Churchill on Soviet Union)

I think the rendition of this type of phrases largely depends on what kind of document they come from. If it is a literary document, a rendition that is too simple is not appropriate. I prefer to render such phrases by adding something like "as the Chinese says" to the actual proverb. That way the different cultural context will not appear too strange for non-Chinese readers while the original literary form can be preserved. :-)