Perhaps you should try some spelling variations:
cua triet » cua viet, su triet
va triet » va thiet, va trien, ve triet
hanh lai » hanh lam, hanh tai, thanh lap
van hanh » van thanh, ban hanh, van anh
luc van » luoc van, luu van, duc van
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
sang ma » tang ma, sang tao, mang may
nang ma » tang ma, nang cao, mang may
cac luc » cau luc, coc luc, cac nuoc
sach 2 » sach y

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 2 ((nang ma) or (sang ma)) hoa. hieu va cac luc van hanh lai ((cua triet) OR (va triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach 2 ((nang ma) OR (sang ma)) hoa. hieu va cac luc van hanh lai ((cua triet) OR (va triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach 2 ((nang ma) or (sang ma)) hoa. hieu va cac luc van hanh lai ((cua triet) OR (va triet))".
• Adding a wildcard symbol may retrieve word variants: tu sach 2 ((nang ma) or (sang ma)) hoa. hieu va cac luc van hanh lai ((cua triet) OR (va triet))*.