Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hieu van » hieu va, thien van, lieu va
va triet » va thiet, va trien, ve triet
tang ma » mang may, tang van
nang ma » sang ma, nang cao, mang may
sach ky » sac ky, sach y, sach ty
cau luc » cau phuc
va hanh » van hanh, va thanh, va danh
hanh ve » hanh vi, hanh va, hanh kem
ve va » ve van, te va, ke va

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

• Performing a fuzzy search may retrieve terms with similar spellings: thuat sach ky ((nang ma) or (tang ma)) hoi. hieu van ((cau luc) OR (cau truc)) va hanh ve va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ky ((nang ma) OR (tang ma)) hoi. hieu van ((cau luc) OR (cau truc)) va hanh ve va triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ky ((nang ma) or (tang ma)) hoi. hieu van ((cau luc) OR (cau truc)) va hanh ve va triet*".