Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
viet cua » viec cua, viet ca, viet qua
va dinh » van dinh, va tinh, vu dinh
ty sang » ty xang, ty hang, duy sang
sang ma » tang ma, nang ma, sang tao
va kinh » va tinh, qua kinh
sach ty » sach y, sach tu, sach thu
cua te » cua tu
ve cac » vien cac
ma hoi » mai hoi, xa hoi, ma hoa

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 ty sang ma hoi. hieu ((ve cac) OR (va cac)) dac ((va dinh) or (va kinh)) viet cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty sang ma hoi. hieu ((ve cac) OR (va cac)) dac ((va dinh) OR (va kinh)) viet cua te*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty sang ma hoi. hieu ((ve cac) OR (va cac)) dac ((va dinh) or (va kinh)) viet cua te*".