Simple little things like cards, hand-written letters, a single rose or a thoughtful chocolate candy bar go a long way for me. Just the fact that you ask that tells mr you're a very thoughtful person. Good luck and best wishes.
As I've known women, as long as they know that you've exerted effort, they'll most likely appreciate it. It would be good to know the favorites of the girl, like the color, the song, etc. Once you know her favorites, it would easier for you to find a gift that will make her glad. Relax, if you couldn't find a red bag, if red is her favorite, then the closest color would be good.
It depend's on her age. If it's a woman there are several thing's. A friendship card, maybe a funny one, if she like's funny. If she's 18 or under, a lot of one's I know like receiving small stuffed animal's. A new video game if they are into game's. A picture of her favorite flower, or animal, wolf, bear, just something that you know she like's.
As long as it's something that you obviously put thought into the actual gift shouldn't matter. Nothing is more annoying than opening a gift & your first thought is "gee, looks like he bought the first thing he saw"