Perhaps you should try some spelling variations:
may thoi » gay thoi, may thi, tay thoi
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
hoc sac » hoc sach, hoc cac, hoc mac
ky mang » ky nang, ke mang, ky dang
hieu ca » hieu cac, hieu cua, hieu va
dinh vi » dinh ve, dinh viet, dinh tri
sac ky » cac ky, sai ky
ca nam » cua nam, cai nam, ha nam

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

• Performing a fuzzy search may retrieve terms with similar spellings: hoc sac ky mang may thoi. hieu ca nam thuc dan ((hanh vi) or (dinh vi)) hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc sac ky mang may thoi. hieu ca nam thuc dan ((hanh vi) OR (dinh vi)) hoa viet.
• Adding a wildcard symbol may retrieve word variants: hoc sac ky mang may thoi. hieu ca nam thuc dan ((hanh vi) or (dinh vi)) hoa viet*.