Perhaps you should try some spelling variations:
va triet » va thiet, va trien, ve triet
thu sach » tu sach, thuat sach, thuoc sach
cau luc » cau truc, cau phuc
hieu va » lieu va, hieu qua
tu cach » tu cac
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
luc ca » luc cao, luc cua, luc va
dan vi » doan vi, dan va, gan vi
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 cach) or (thu sach)) ky lang xa hoi. hieu va cau luc ca ((dan vi) OR (don vi)) va triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thu sach)) ky lang xa hoi. hieu va cau luc ca ((dan vi) OR (don vi)) va triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu cach) or (thu sach)) ky lang xa hoi. hieu va cau luc ca ((dan vi) OR (don vi)) va triet".
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (thu sach)) ky lang xa hoi. hieu va cau luc ca ((dan vi) OR (don vi)) va triet*.