Perhaps you should try some spelling variations:
ve triet » va trien, su triet
thuc dan » thuc hanh, hoc dan, thuc vat
ky lang » ky nang, ky tang, tay lang
danh de » hanh de, dan de, dang de
ky dang » ky nang, ky danh
hieu ve » hieu va, hieu van
thuc va » thuc vat, thuc day
te sac » te sach, te cac, te san
ve cam » ve cham, ve cac, va cam

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sac ((ky lang) or (ky dang)) xa hoi. hieu ve cam ((thuc va) OR (thuc dan)) danh de ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ((ky lang) OR (ky dang)) xa hoi. hieu ve cam ((thuc va) OR (thuc dan)) danh de ve triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ((ky lang) or (ky dang)) xa hoi. hieu ve cam ((thuc va) OR (thuc dan)) danh de ve triet".
• Adding a wildcard symbol may retrieve word variants: te sac ((ky lang) or (ky dang)) xa hoi. hieu ve cam ((thuc va) OR (thuc dan)) danh de ve triet*.