Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
hieu ve » hieu va, hieu van
cuu tre » cua tre, cau treo
va suc » va su
nang o » nang co, nang ho, nang ro
ve cac » vien cac
cac tu » cac thu, cach tu, cac du
va dan » ca dan, va dao, va dau
dan di » danh di, dan da, dan de
o hoi » co hoi, o hoc, o hai

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((va suc) or (va cac)) ky nang o hoi. hieu ve cac tu va dan di ((cuu tre) OR (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((va suc) OR (va cac)) ky nang o hoi. hieu ve cac tu va dan di ((cuu tre) OR (cau tren))*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((va suc) or (va cac)) ky nang o hoi. hieu ve cac tu va dan di ((cuu tre) OR (cau tren))*".