Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
va tinh » may tinh
va dinh » van dinh, va kinh, vu dinh
sach ky » sac ky, sach y, sach ty
tu sach » thu sach, su sach, te sach
hieu ve » hieu va, hieu van
lang xa » lang ha, dang xay, lang van
nang xa » nang x, nang ma, mang xa
cac luc » cau luc, coc luc, cac nuoc
ve cac » va cac, vien cac
vi su » va su, ve su, ki su

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 ((nang xa) or (lang xa)) hoi. hieu ve cac luc ((va dinh) OR (va tinh)) vi su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky ((nang xa) OR (lang xa)) hoi. hieu ve cac luc ((va dinh) OR (va tinh)) vi su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky ((nang xa) or (lang xa)) hoi. hieu ve cac luc ((va dinh) OR (va tinh)) vi su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach ky ((nang xa) or (lang xa)) hoi. hieu ve cac luc ((va dinh) OR (va tinh)) vi su triet*.