Perhaps you should try some spelling variations:
thuoc sach » hoc sach, nuoc sach, thuat sach
toc sach » hoc sach, doc sach, nuoc sach
tinh ket » dinh ket, tinh yeu, tinh yen
va trien » va truyen, va thiet, va tuyen
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
tuc va » thuc va, truc va, duc va
ket va » ket van
va cao » va cac, va co, va dao

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

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