Perhaps you should try some spelling variations:
sach thi » sach thu, sach tai, sach tham
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
hang xa » hoang xa, hang va, hang ca
hieu ve » hieu va, hieu van
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: tu ((sach thi) or (sach thieu)) hang xa hoi. hieu ve nam thuc dan hanh vi ((cua viet) or (cua vat))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach thi) OR (sach thieu)) hang xa hoi. hieu ve nam thuc dan hanh vi ((cua viet) OR (cua vat)).
• Adding a wildcard symbol may retrieve word variants: tu ((sach thi) or (sach thieu)) hang xa hoi. hieu ve nam thuc dan hanh vi ((cua viet) or (cua vat))*.