Perhaps you should try some spelling variations:
sang mai » sang ma, sang tai, lang mai
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
dan hanh » dang hanh, dan khanh, dan thanh
cua viet » ca viet, hoa viet, cua dieu
su sach » so sach, vu sach
mai hoi » mai khoi, dai hoi, lai hoi
hieu ve » hieu va, hieu van
va viet » hoa viet, san viet, mai viet
ve nam » he nam, va nam, le nam

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

• Performing a fuzzy search may retrieve terms with similar spellings: su sach _ sang mai hoi. hieu ve nam thuc dan hanh vi ((((cua viet) or (cua vat))) or (va viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach _ sang mai hoi. hieu ve nam thuc dan hanh vi ((((cua viet) OR (cua vat))) OR (va viet)).
• Adding a wildcard symbol may retrieve word variants: su sach _ sang mai hoi. hieu ve nam thuc dan hanh vi ((((cua viet) or (cua vat))) or (va viet))*.