Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh dao » lanh dao, thanh dat, thanh dam
hanh dai » hanh tai, vanh dai, thanh dat
sach ty » sach y, sach tu, sach thu
truc va » thuc va, thuc vat, trung va
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
sai ky » sac ky
va cau » van cau, va cac, va dau

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 ty) or (sai ky)) nang ma hoi. hieu va cau truc va ((hanh dai) OR (hanh dao)) cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sai ky)) nang ma hoi. hieu va cau truc va ((hanh dai) OR (hanh dao)) cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sai ky)) nang ma hoi. hieu va cau truc va ((hanh dai) OR (hanh dao)) cua triet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sai ky)) nang ma hoi. hieu va cau truc va ((hanh dai) OR (hanh dao)) cua triet*.