Perhaps you should try some spelling variations:
vat hanh » vat thanh, van hanh, va hanh
cac thuc » cach thuc, cac thu, can thuc
doi cua » dai cua, hoi cua
su sach » so sach, vu sach
mang xa » lang xa, mang may, dang xay
hieu ve » hieu va, hieu van
sach v » sach va, sach y, sach 2
ve cac » va cac, vien cac
di cua » dai cua, de cua, do 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: su sach v ((mang xa) OR (nang x)) hoi. hieu ve cac thuc vat hanh ((di cua) OR (doi cua)) triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach v ((mang xa) or (nang x)) hoi. hieu ve cac thuc vat hanh ((di cua) OR (doi cua)) triet~".
• Adding a wildcard symbol may retrieve word variants: su sach v ((mang xa) or (nang x)) hoi. hieu ve cac thuc vat hanh ((di cua) OR (doi cua)) triet*.