Perhaps you should try some spelling variations:
than changed » than change, has changed, man changed
changed role » changed rome, changed file, changing role
long tail » long haul
role chen » role china, role can, role cle
john song » john wong, john bonn
long tip » long trip, long time, long did

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((long tip) or (long tail)) than changed role chen ((john ngosong) OR (john song)) sein ;~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((long tip) OR (long tail)) than changed role chen ((john ngosong) OR (john song)) sein ;.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((long tip) or (long tail)) than changed role chen ((john ngosong) OR (john song)) sein ;".
• Adding a wildcard symbol may retrieve word variants: ((long tip) or (long tail)) than changed role chen ((john ngosong) OR (john song)) sein ;*.