Perhaps you should try some spelling variations:
thanh phan » thanh pho, thanh san, thanh toan
toc sach » hoc sach, doc sach, thuoc sach
va thanh » gia thanh, ban thanh, va tinh
tay lang » tai lang, tay tang, tay quang
phan cua » nhan cua, than cua, phat cua
hieu van » thien van, lieu va, hieu ve
nam thuc » nam thuoc, am thuc, nam thu
ky tang » ky nang, ky dang, kho tang
hieu va » lieu va, hieu qua
thuc va » thuc vat, thuc dan, thuc day
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ((tay lang) or (ky tang)) xa hoi. ((hieu van) OR (hieu va)) nam thuc va thanh phan cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((tay lang) OR (ky tang)) xa hoi. ((hieu van) OR (hieu va)) nam thuc va thanh phan cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((tay lang) or (ky tang)) xa hoi. ((hieu van) OR (hieu va)) nam thuc va thanh phan cua te".
• Adding a wildcard symbol may retrieve word variants: toc sach ((tay lang) or (ky tang)) xa hoi. ((hieu van) OR (hieu va)) nam thuc va thanh phan cua te*.