Perhaps you should try some spelling variations:
sang tao » hang tai
thu sach » thuat sach, thuoc sach, thu hoach
va hanh » van hanh, va thanh, va danh
cao duc » dao duc, cao suc, giao duc
hieu ve » hieu va, hieu van
tu sach » su sach, te sach, tu cach
ve cao » va cao, ve bao, ve cac
vi cua » vai cua, di cua
cua te » cua tu

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) or (thu sach)) ky ((mang may) or (sang tao)) hoi. hieu ve cao duc va hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu sach)) ky ((mang may) OR (sang tao)) hoi. hieu ve cao duc va hanh vi cua te.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu sach)) ky ((mang may) or (sang tao)) hoi. hieu ve cao duc va hanh vi cua te*.