Bulgaria
I would put Bulgarian rose oil perfume on the list for Bulgaria because it is the kind of thing that feels useful once you are home, not just another airport purchase. Small bottles are best. A local scent, soap or oil feels personal, but it is still easy to pack and usually does not cost airport-perfume money. The reason it works is that it gives you a quick reminder of the trip without needing to keep a fragile ornament safe forever.
This is exactly the sort of thing I like bringing back from Bulgaria: small enough to fit in a bag, but specific enough to remind you where you bought it. Cured meats are popular holiday finds, but they are also the category most likely to get caught by changing import rules. It is also the kind of thing you can talk about when someone asks what you brought back, because there is usually a little story attached to where you found it.
Bulgaria
Pepper and tomato spread served with bread, cheese or grilled meat.
Bulgaria
When I think of an easy, crowd-pleasing thing to bring back from Bulgaria, sharena sol spice blend is a good pick because it does not need much explanation when you hand it over. The best version is usually the sealed jar, tin or packet from a normal supermarket, spice stall or food hall, not the most expensive tourist version. I would rate it higher when it is locally made, clearly labelled and easy to use at home, and lower when it is just tourist packaging.
Bulgaria
Bulgarian yoghurt starter is worth adding because it feels like something you actually noticed while travelling through Bulgaria, rather than a generic souvenir. This is more of a buy-in-the-UK idea now unless current food rules clearly allow it. It still belongs in the database because people search for it after tasting it abroad. The ideal version is modestly priced, not too bulky, and good enough that you would buy it again even without the holiday memory.