Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
van hanh » van thanh, van anh, van ban
dang xay » dang van, van xay
ban hanh » ban hang
cau phuc » cau truc, chau phu, huu phuc
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
lang ha » long ha
hieu va » lieu va, hieu qua
va cau » van cau, va cac, va dau
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: tu sach ky ((dang xay) or (lang ha)) hoi. hieu va cau phuc ((ban hanh) or (van hanh)) vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((dang xay) OR (lang ha)) hoi. hieu va cau phuc ((ban hanh) OR (van hanh)) vi cua triet.
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((dang xay) or (lang ha)) hoi. hieu va cau phuc ((ban hanh) or (van hanh)) vi cua triet*.