Perhaps you should try some spelling variations:
dua tren » dung tren
hieu van » thien van, lieu va, hieu ve
toc sach » hoc sach, doc sach, thuoc sach
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
nam duc » nam duoc, pham duc, nam thuc
va lang » va nang, hoa lang
lang du » lang duc, nang du, tang du
tu sach » thu sach, su sach, te sach
du dua » de dua, du dia, duc duat

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (toc sach)) ky lang xa hoi. ((hieu van) OR (hieu va)) nam duc va lang du dua tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (toc sach)) ky lang xa hoi. ((hieu van) OR (hieu va)) nam duc va lang du dua tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (toc sach)) ky lang xa hoi. ((hieu van) OR (hieu va)) nam duc va lang du dua tren".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (toc sach)) ky lang xa hoi. ((hieu van) OR (hieu va)) nam duc va lang du dua tren*.