Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
thuoc va » thuoc ma, thuong va, thuoc tai
tu sach » thu sach, su sach, te sach
hanh ve » hanh vi, hanh va, hanh kem
thuc va » thuc vat, thuc dan, thuc day
cuu tre » cua tre, cau tren, cau treo
sach ly » sach y, sach lo, sach ty
qua nam » quan nam, cua nam, quang nam
tang ma » mang may, tang van
ly tang » le tang, ly hang, ly vang
ma hoi » mai hoi, xa hoi, ma hoa

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 ly tang ma hoi. hieu qua nam ((thuoc va) OR (thuc va)) ((thanh van) or (hanh ve)) cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ly tang ma hoi. hieu qua nam ((thuoc va) OR (thuc va)) ((thanh van) OR (hanh ve)) cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ly tang ma hoi. hieu qua nam ((thuoc va) OR (thuc va)) ((thanh van) or (hanh ve)) cuu tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ly tang ma hoi. hieu qua nam ((thuoc va) OR (thuc va)) ((thanh van) or (hanh ve)) cuu tre*.