Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
tinh yen » tinh yeu, tinh dien, tinh son
va tuyen » va truyen, tac tuyen, ke tuyen
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
va cao » va cac, va co, va dao
tuc va » thuc va, truc va, duc va
yen va » nen va, gen va, yen vy

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 ky lang xa hoi. hieu va cao ((tuc va) or (tuc xa)) tinh yen va tuyen~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky lang xa hoi. hieu va cao ((tuc va) OR (tuc xa)) tinh yen va tuyen.
• Adding a wildcard symbol may retrieve word variants: toc sach ky lang xa hoi. hieu va cao ((tuc va) or (tuc xa)) tinh yen va tuyen*.