Perhaps you should try some spelling variations:
hoc sach » hoc sinh, hoc cac, hoc anh
hanh vai » hanh vi, hanh va, hanh tai
va triet » va thiet, va trien, ve triet
so sach » so sanh, bo sach
co sach » bo sach, cuon sach
nang ma » tang ma, sang ma, nang cao
hieu va » lieu va, hieu qua
cao tuc » dao tuc, cao duc, cao suc
xa hanh » xa thanh, xa khanh, va hanh
y nang » ky nang, ly nang, v nang
ma hoi » mai hoi, xa hoi, ma hoa
va cao » va cac, va co, va dao
vai va » mai va, dai va, hai va

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((so sach) or (((co sach) OR (hoc sach)))) y nang ma hoi. hieu va cao tuc xa hanh vai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((so sach) OR (((co sach) OR (hoc sach)))) y nang ma hoi. hieu va cao tuc xa hanh vai va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((so sach) or (((co sach) OR (hoc sach)))) y nang ma hoi. hieu va cao tuc xa hanh vai va triet".
• Adding a wildcard symbol may retrieve word variants: ((so sach) or (((co sach) OR (hoc sach)))) y nang ma hoi. hieu va cao tuc xa hanh vai va triet*.