Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
sach tri » sach tai, sach tren, sach truc
hien cac » thien cac, vien cac, hieu cac
vu sach » vu bach, su sach, vu khach
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
cac duc » cac du, cao duc, cac dac
va hanh » van hanh, va thanh, va danh
tai cua » thai cua, tri cua, dai cua

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: vu sach tri ((nang xa) OR (nang ma)) hoi. hieu hien cac duc va hanh ((tai cua) OR (tai cuc)) su~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach tri ((nang xa) OR (nang ma)) hoi. hieu hien cac duc va hanh ((tai cua) or (tai cuc)) su~".
• Adding a wildcard symbol may retrieve word variants: vu sach tri ((nang xa) OR (nang ma)) hoi. hieu hien cac duc va hanh ((tai cua) or (tai cuc)) su*.