Perhaps you should try some spelling variations:
dan hanh » dang hanh, dan khanh, dan thanh
cua viet » hoa viet, cua vat, cua dieu
nam thuc » nam thuoc, am thuc, nam thu
thuc dan » thuc hanh, hoc dan, thuc vat
ca viet » va viet, co viet, hoa viet
nang xa » nang x, nang ma, mang xa
lang xa » lang ha, dang xay, lang van
hieu ve » hieu va, hieu van
sanh y » sinh y, anh y, hanh y
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: do sanh y ((nang xa) or (lang xa)) hoi. hieu ve nam thuc dan hanh vi ((cua viet) or (ca viet))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: do sanh y ((nang xa) OR (lang xa)) hoi. hieu ve nam thuc dan hanh vi ((cua viet) OR (ca viet)).
• Adding a wildcard symbol may retrieve word variants: do sanh y ((nang xa) or (lang xa)) hoi. hieu ve nam thuc dan hanh vi ((cua viet) or (ca viet))*.