Perhaps you should try some spelling variations:
bulgaricae » bulgarica, bulgarische, bulgarian, bulgareicae, vulgaricae, bulgarieicae
bulgaria » bulgareia, vulgaria, bulgarieia
bulgar » bulgare, vulgar, bulgarie
bulger » bulges
bilgere » bilgeri, billigere, hilgere, pilgere, kilgere
bilger » hilger, pilger, kilger

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: ((bulgaria OR bulgaricae) OR ((bulgar OR bulger) OR (bulge OR (bilgere OR bilger)))).
• Adding a wildcard symbol may retrieve word variants: ((bulgaria or bulgaricae) or ((bulgar or bulger) or (bulge or (bilgere or bilger))))*.