Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
dung tren » dung trong, dung trung
cau thuc » cau truc, cuu thuc, can thuc
vu sach » vu bach, su sach, vu khach
sach ky » sac ky, sach y, sach ty
ky lang » ky nang, ky dang, ky tang
lang xa » lang ha, dang xay, lang van
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
va tinh » may tinh
tinh va » tich va, trinh van, trinh vat
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: vu sach ky lang xa hoi. hieu va cau thuc va tinh va ((dung tren) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ky lang xa hoi. hieu va cau thuc va tinh va ((dung tren) OR (cua triet)).
• Adding a wildcard symbol may retrieve word variants: vu sach ky lang xa hoi. hieu va cau thuc va tinh va ((dung tren) or (cua triet))*.