Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
sach thu » sach thue, sach thieu, sach tham
va triet » va thiet, va trien, ve triet
nang xa » lang xa, nang ma, mang xa
hieu ve » hieu va, hieu van
truc va » thuc va, thuc vat, trung va
va hanh » van hanh, va thanh, va danh
ve cau » ke cau, va cau, ve cac
vi va » vi van, vai va, vu va

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: thu sach thu ((nang xa) OR (nang x)) hoi. hieu ve cau truc va hanh vi va triet~.
• Adding a wildcard symbol may retrieve word variants: thu sach thu ((nang xa) or (nang x)) hoi. hieu ve cau truc va hanh vi va triet*.