Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
thu sach » tu sach, thuoc sach, thu hoach
dang xay » dang van, van xay
danh vai » danh sai, danh va, doanh van
hieu van » thien van, lieu va, hieu ve
lo dang » lop dang, le dang, xo dang
xay hoi » xa hoi, tay hoi, cay phoi
hieu va » lieu va, hieu qua
chu duc » thu duc, chua duoc, cuu duoc
va danh » va dinh, va dan, va hanh
vai cua » dai cua, hai cua, lai cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((thu sach) OR (thuat sach)) lo dang xay hoi. ((hieu van) or (hieu va)) chu duc va danh vai cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((thu sach) OR (thuat sach)) lo dang xay hoi. ((hieu van) OR (hieu va)) chu duc va danh vai cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((thu sach) OR (thuat sach)) lo dang xay hoi. ((hieu van) or (hieu va)) chu duc va danh vai cua te".
• Adding a wildcard symbol may retrieve word variants: ((thu sach) OR (thuat sach)) lo dang xay hoi. ((hieu van) or (hieu va)) chu duc va danh vai cua te*.