Perhaps you should try some spelling variations:
trinh dai » trinh tai, trinh di, trinh da
va trinh » van trinh, va tinh, lap trinh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
mai hoi » mai khoi, dai hoi, mai doi
lai hoi » dai hoi, lai hoa, lai roi
hieu ve » hieu va, hieu van
cam duc » cam xuc, cao duc, pham duc
cua tre » cua te, cuu tre, cua triet
ve cam » ve cham, ve cac, va cam

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 ky nang ((mai hoi) or (lai hoi)). hieu ve cam duc va trinh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang ((mai hoi) OR (lai hoi)). hieu ve cam duc va trinh dai cua tre*.