Perhaps you should try some spelling variations:
study contract » study contracting, study context, study abstract
contract based » control based, content based, context based
yang yang » wang yang, wang yan
young ghi » young choi, hong ghi, young get
based a » based ai, based ad, based na
a young » _ young
wang » wan, lang

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

• Performing a fuzzy search may retrieve terms with similar spellings: (wang OR wing) ((yao yang) OR (yang yang)) study contract based a young ghi ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "(wang OR wing) ((yao yang) OR (yang yang)) study contract based a young ghi ;".
• Adding a wildcard symbol may retrieve word variants: (wang OR wing) ((yao yang) OR (yang yang)) study contract based a young ghi ;*.