Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach tham
hanh tai » thanh tai, hang tai, han tai
va triet » va thiet, va trien, ve triet
nang ca » nang cao, nang cap, nang cai
hieu va » lieu va, hieu qua
cam tuc » cam xuc, cam tu, nam thuc
va hanh » van hanh, va thanh, va danh
ca hoi » cau hoi, cua hoi, xa hoi
va cam » va cham, va cac, va cao
tuc va » thuc va, truc va, tuc xa
tai va » thai va, mai va, tri va

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach thi) or (sach thieu)) nang ca hoi. hieu va cam tuc va hanh tai va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thi) OR (sach thieu)) nang ca hoi. hieu va cam tuc va hanh tai va triet.
• Adding a wildcard symbol may retrieve word variants: tu ((sach thi) or (sach thieu)) nang ca hoi. hieu va cam tuc va hanh tai va triet*.