Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
hanh via » hanh vi, hanh va, anh va
thuc dan » thuc hanh, thuc vat
may thoi » gay thoi, may thi, tay thoi
via cua » gia cua, gian cua, giau cua
va nham » va cham, va tham, va nha
hieu va » lieu va, hieu qua
ke mang » ke nang, ke trang
tu sach » thu sach, su sach, te sach
tu sac » tu cac, tu san, tu bac

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sac) or (tu sach)) ke mang may thoi. hieu va nham ((thuc dan) OR (hoc dan)) hanh via cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sac) OR (tu sach)) ke mang may thoi. hieu va nham ((thuc dan) OR (hoc dan)) hanh via cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sac) or (tu sach)) ke mang may thoi. hieu va nham ((thuc dan) OR (hoc dan)) hanh via cua triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sac) or (tu sach)) ke mang may thoi. hieu va nham ((thuc dan) OR (hoc dan)) hanh via cua triet*.