Perhaps you should try some spelling variations:
bulgariae » bulgaria, bulgarian, bulgarie
bulgaricae » bulgarica, bulgarische, bulgaria
bulges » bulge
bilgere » bilger, billigere
bilgeri » biggeri, bilger

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: ((bulgariae OR bulgaricae) OR (bulges OR (bilgere OR bilgeri))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((bulgariae OR bulgaricae) or (bulges or (bilgere or bilgeri)))".
• Adding a wildcard symbol may retrieve word variants: ((bulgariae OR bulgaricae) or (bulges or (bilgere or bilgeri)))*.