Funny you should mention Woodruff, because I just recently found some potted specimens and couldn't wait to get them home and pot them - after snipping off a few sprouts so I can dry them.
It's very hard to find here in Australia, so I was stoked when I got it.
The sweet smell of Woodruff is because of the high levels of coumarin in it. Coumarin is also present in tonka beans, vanilla grass, cassia bark, and a few other plants. It's a beautiful smell, and in Woodruff it is mixed with the fresh grassy greenness that makes it a delicious-smelling herb.
But beware, coumarin is a powerful anti-coagulant and is moderately toxic to the liver and kidneys, and as a result of the high levels of this substance in tonka beans the spice has been banned in the U.S. for quite a few years.
Try finding something with a lot of tonka bean in the notes and you'll find a lot of that sweet almondy-vanilla Woodruff aroma in it.
PS: coumarin is used quite a lot in perfumery, and you will find it listed as an ingredient on the back of many boxes of fragrances.