Perhaps you should try some spelling variations:
cua viet » ca viet, hoa viet, cua vat
nam thuc » nam thuoc, am thuc, nam thu
lang mai » lang dai, lang hai, lang man
hieu van » thien van, lieu va, hieu ve
hanh de » hanh ve, hanh kem
hanh le » thanh le, hanh ve, manh le
thuc va » thuc vat, thuc dan, thuc day
tu sach » thu sach, su sach, te sach
sach lo » sach dao, sach doi, sach hoi
hieu va » lieu va, hieu qua
mai hoi » mai khoi, dai hoi, lai hoi
lo lang » o lang, so lang, le 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 lo lang mai hoi. ((hieu van) or (hieu va)) nam thuc va ((hanh le) OR (hanh de)) cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach lo lang mai hoi. ((hieu van) OR (hieu va)) nam thuc va ((hanh le) OR (hanh de)) cua viet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach lo lang mai hoi. ((hieu van) or (hieu va)) nam thuc va ((hanh le) OR (hanh de)) cua viet*".