Perhaps you should try some spelling variations:
teaching change » teaching chinese, teaching chapter, teaching china
teaching chang » teaching china, teaching chunks, teaching doing
time last » time list, time past, time lost
roberto e » robert e, roberto n, roberto f
tan yang » dan yang, tan ying, tan yong
fan ying » fan xing, ran ying, tan ying
dido » did, didn, dino

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

• If you are trying to use Boolean operators, they must be ALL CAPS: ((tan yang) OR (fan ying)) dido time last ((teaching chang) OR (teaching change)) roberto e ;~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tan yang) or (fan ying)) dido time last ((teaching chang) OR (teaching change)) roberto e ;~".
• Adding a wildcard symbol may retrieve word variants: ((tan yang) or (fan ying)) dido time last ((teaching chang) OR (teaching change)) roberto e ;*.