Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
ve triet » va trien, su triet
hanh lai » hanh lam, hanh tai, thanh lap
va triet » va thiet, va trien, cua triet
sach ty » sach y, sach tu, sach thu
va pham » van pham, va phat, va phap
va hanh » van hanh, va thanh, va danh
ty sang » ty xang, ty hang, duy sang
hieu va » lieu va, hieu qua
me hoi » le hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ty sang ((me hoi) or (xa hoi)). hieu va pham duc va hanh lai ((ve triet) or (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ty sang ((me hoi) OR (xa hoi)). hieu va pham duc va hanh lai ((ve triet) OR (va triet)).
• Adding a wildcard symbol may retrieve word variants: thu sach ty sang ((me hoi) or (xa hoi)). hieu va pham duc va hanh lai ((ve triet) or (va triet))*.