Perhaps you should try some spelling variations:
nham thuc » nhan thuc, nam thuc, nham thu
hanh vai » hanh vi, hanh va, hanh tai
thu sach » tu sach, thuat sach, thuoc sach
tu cach » tu cac
va hanh » van hanh, va thanh, va danh
thuc va » thuc vat, thuc dan, thuc day
va nham » va cham, va tham, va nha
hieu va » lieu va, hieu qua
hang ca » hang va, hang tai, hang dau
so viet » hoc viet
vai so » dai so, tai so, va so

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu cach) or (thu sach)) thi ((hang ca) OR (nang cao)) hoi. hieu va nham thuc va hanh vai so viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thu sach)) thi ((hang ca) OR (nang cao)) hoi. hieu va nham thuc va hanh vai so viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (thu sach)) thi ((hang ca) OR (nang cao)) hoi. hieu va nham thuc va hanh vai so viet*".