http://www.mangago.me/tag/
Just type any particular tag into the box to the right. Otherwise you can also get to the screen by clicking tags from the "top tags" box of any manga and search
As far as I know there's no tag dicitionary on mangago, so you just need to be creative xD
http://www.mangago.me/tag/ and add the one you want
There's a thing like that on Baka Manga Updates, so you may want to use that (also you can search by tags combined, pretty useful)
I've been trying to go to the tags page so i can look up certain manga that meet the criteria, but i just can't figure out how to her there. Can anyone help? Also, anyone have a good yaoi they recommend?