Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
cau thuc » cau truc, cuu thuc, can thuc
dua tren » dung tren
tinh va » tich va, trinh van, trinh vat
va tinh » may tinh
thuc va » thuc vat, thuc dan, thuc day
sach ky » sac ky, sach ty, sach kem
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
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) OR (sach y)) lang xa hoi. hieu va cau thuc va tinh va ((dua tren) or (cua triet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu ((sach ky) OR (sach y)) lang xa hoi. hieu va cau thuc va tinh va ((dua tren) OR (cua triet)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu ((sach ky) OR (sach y)) lang xa hoi. hieu va cau thuc va tinh va ((dua tren) or (cua triet))".
• Adding a wildcard symbol may retrieve word variants: vu ((sach ky) OR (sach y)) lang xa hoi. hieu va cau thuc va tinh va ((dua tren) or (cua triet))*.