Perhaps you should try some spelling variations:
"acs symposium series" » "acs symposium semi", "acs symposium sas", "acs symposium spire", "das symposium series", "lakes symposium series", "games symposium series"
"bacus symposium series" » "bacus symposium semi", "bacus symposium sas", "bacus symposium spire"
"backs symposium sss" » "spaces symposium sss", "lakes symposium sss", "bibos symposium sss", "backs symposium sas"

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: (((("acs symposium series") OR ("bacus symposium series"))) OR ("backs symposium sss"))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((((\"acs symposium series\") OR (\"bacus symposium series\"))) or (\"backs symposium sss\"))*".
• Removing quotes may allow a broader search: (((( acs symposium series ) OR ( bacus symposium series ))) or ( backs symposium sss ))*.