Perhaps you should try some spelling variations:
hanh lai » hanh lam, hanh tai, thanh lap
thuc dan » thuc hanh, hoc dan, thuc vat
tu sach » thu sach, su sach, te sach
lai cua » dai cua, hai cua, lai chau
thuc va » thuc vat, thuc day
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu van
hieu va » lieu va, hieu qua
lang xa » lang ha, dang xay, lang van
sach o » sach lo, sac o, sach y
o lang » hoa lang, hoi lang

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 o lang xa hoi. ((hieu ve) or (hieu va)) cau ((thuc va) or (thuc dan)) hanh lai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach o lang xa hoi. ((hieu ve) OR (hieu va)) cau ((thuc va) OR (thuc dan)) hanh lai cua tre.
• Adding a wildcard symbol may retrieve word variants: tu sach o lang xa hoi. ((hieu ve) or (hieu va)) cau ((thuc va) or (thuc dan)) hanh lai cua tre*.