Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
tuc van » thuc van, truc van, tuc va
cac tuc » cac toc, cac tu, cac tac
sach ty » sach y, sach tu, sach thu
hieu va » lieu va
lang xa » lang ha, dang xay, lang van
mang xa » mang may, dang xay, mang cua
vi cua » vai cua, di cua
cua te » cua tu

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

• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty ((mang xa) OR (lang xa)) hoi. ((hieu va) OR (hieu qua)) cac tuc van hanh vi cua te~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty ((mang xa) OR (lang xa)) hoi. ((hieu va) or (hieu qua)) cac tuc van hanh vi cua te~".
• Adding a wildcard symbol may retrieve word variants: toc sach ty ((mang xa) OR (lang xa)) hoi. ((hieu va) or (hieu qua)) cac tuc van hanh vi cua te*.