Perhaps you should try some spelling variations:
brass symposium » iass symposium, praxis symposium, frames symposium
gras symposium » das symposium, aaas symposium, cas symposium
acs symposium » bacus symposium, das symposium, lakes symposium

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: ((((gras symposium) OR (brass symposium))) OR (acs symposium)) (sans OR sams).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((gras symposium) OR (brass symposium))) or (acs symposium)) (sans or sams)".
• Adding a wildcard symbol may retrieve word variants: ((((gras symposium) OR (brass symposium))) or (acs symposium)) (sans or sams)*.