Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
ban hanh » ban hang
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, nang cao, mang may
sang ma » tang ma, sang tao, mang may
hieu va » lieu va, hieu qua
cac duc » cac du, cao duc, cac dac
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach ky ((nang ma) OR (sang ma)) hoi. hieu va cac duc ((ban hanh) or (van minh)) vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky ((nang ma) OR (sang ma)) hoi. hieu va cac duc ((ban hanh) OR (van minh)) vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky ((nang ma) OR (sang ma)) hoi. hieu va cac duc ((ban hanh) or (van minh)) vi cua triet".
• Adding a wildcard symbol may retrieve word variants: su sach ky ((nang ma) OR (sang ma)) hoi. hieu va cac duc ((ban hanh) or (van minh)) vi cua triet*.