Perhaps you should try some spelling variations:
shang hai » shang kai, dang hai, chang ha
yan yang » yang yang, yao yang, dan yang
oil coal » oil oil, oil can, oil chad
plam oil » plant oil, palm oil, peak oil
hong hai » zhong tai, dang hai, hong tan
hong yu » wong yue
wang » wing, 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 yan yang ((oil coal) or (oil cost)) plam oil ((((hong hai) OR (shang hai))) or (hong yu)) ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: wang yan yang ((oil coal) OR (oil cost)) plam oil ((((hong hai) OR (shang hai))) OR (hong yu)) ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "wang yan yang ((oil coal) or (oil cost)) plam oil ((((hong hai) OR (shang hai))) or (hong yu)) ;".
• Adding a wildcard symbol may retrieve word variants: wang yan yang ((oil coal) or (oil cost)) plam oil ((((hong hai) OR (shang hai))) or (hong yu)) ;*.