Perhaps you should try some spelling variations:
"acta slavica estonia" » "acta slovenia estonia", "anna slavina estonia", "art slavic estonia", "et slavica estonia"
"balto slavic estonia" » "balto slovenia estonia"
"balto latvia estonia" » "health latvia estonia", "faso latvia estonia", "haiti latvia estonia"

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: (("acta slavica estonia") OR ((("balto slavic estonia") OR ("balto latvia estonia")))).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"acta slavica estonia\") or (((\"balto slavic estonia\") OR (\"balto latvia estonia\"))))".
• Removing quotes may allow a broader search: (( acta slavica estonia ) or ((( balto slavic estonia ) OR ( balto latvia estonia )))).
• Adding a wildcard symbol may retrieve word variants: (("acta slavica estonia") or ((("balto slavic estonia") OR ("balto latvia estonia"))))*.