Perhaps you should try some spelling variations:
thanh hai » thanh phan, thanh hoa, thanh san
van thanh » ban thanh, van tuan
hieu van » hieu va, thien van, lieu va
nam thuc » nam thuoc, am thuc, nam thu
kho lang » kho tang, cho lang, tho lang
lang mai » lang dai, lang hai, lang man
thuc van » thuc vat, thuc dan, thuc va
tu sach » thu sach, su sach, te sach
mai hoi » mai khoi, dai hoi, lai hoi
vu sach » vu bach, su sach, vu khach
cua tu » cua tuc, cua cu, cua te
cua su » qua su

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) or (vu sach)) kho lang mai hoi. hieu van nam thuc van thanh hai ((cua tu) OR (cua su))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (vu sach)) kho lang mai hoi. hieu van nam thuc van thanh hai ((cua tu) OR (cua su)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (vu sach)) kho lang mai hoi. hieu van nam thuc van thanh hai ((cua tu) OR (cua su))".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (vu sach)) kho lang mai hoi. hieu van nam thuc van thanh hai ((cua tu) OR (cua su))*.