Perhaps you should try some spelling variations:
safe working » save working, usage working, safe walking
long working » among working, doing working, sang working
china chang » chin chang, china zhang, china changqi
best think » best thing
chang c » chang _, anhang c, chang ha
c best » 3 best, 4 best, 1 best

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

• The words AND, OR and NOT may confuse the search; try adding quotes: "can china chang c best think ((long working) OR (safe working)) yue ;~".
• Adding a wildcard symbol may retrieve word variants: can china chang c best think ((long working) OR (safe working)) yue ;*.