Perhaps you should try some spelling variations:
"big 4 conference" » "big ds conference" (Expand Search), "big 1984 conference" (Expand Search), "big 1st conference" (Expand Search), "bi 4 conference" (Expand Search)
"ba 4 conference" » "ba ds conference" (Expand Search), "ba 1984 conference" (Expand Search), "ba 1st conference" (Expand Search), "ba 1 conference" (Expand Search), "ba 5 conference" (Expand Search), "ba _ conference" (Expand Search), "ba 24 conference" (Expand Search)
"a 4 conference" » "a ds conference" (Expand Search), "a 1984 conference" (Expand Search), "a 1st conference" (Expand Search), "a 24 conference" (Expand Search)

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (("big 4 conference") OR ((("bi _ conference") OR ((("ba 4 conference") OR ("a 4 conference"))))))~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((\"big 4 conference\") OR (((\"bi _ conference\") OR (((\"ba 4 conference\") OR (\"a 4 conference\"))))))*".
• Removing quotes may allow a broader search: (( big 4 conference ) OR ((( bi _ conference ) OR ((( ba 4 conference ) OR ( a 4 conference ))))))*.