Perhaps you should try some spelling variations:
"sources symposium semi" » "studies symposium semi", "southwest symposium semi", "solids symposium semi", "sources symposium sss", "sources symposium sagt"
"backs symposium series" » "backs symposium sss", "backs symposium spire", "backs symposium ssbse", "bacus symposium series", "acs symposium series", "spaces symposium series"
"backs symposium semi" » "bacus symposium semi", "acs symposium semi", "spaces symposium semi", "backs symposium sss", "backs symposium sagt"
"backs symposium sas" » "bacus symposium sas", "acs symposium sas", "spaces symposium sas", "backs symposium sans", "backs symposium sams"

Try widening your search to All Fields.

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: (((("backs symposium series") OR ((("backs symposium semi") OR ("sources symposium semi"))))) OR ("backs symposium sas")).
• Removing quotes may allow a broader search: (((( backs symposium series ) or ((( backs symposium semi ) or ( sources symposium semi ))))) or ( backs symposium sas )).
• Adding a wildcard symbol may retrieve word variants: (((("backs symposium series") or ((("backs symposium semi") or ("sources symposium semi"))))) or ("backs symposium sas"))*.