Perhaps you should try some spelling variations:
thuc dan » thuc hanh, hoc dan, thuc vat
hieu van » thien van, lieu va, hieu ve
dan hanh » dang hanh, dan khanh, dan thanh
cuu thuc » cuu tac
tu sach » thu sach, su sach, tu cach
te sach » toc sach
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
hanh le » thanh le, hanh ve, hanh de
hieu va » lieu va, hieu qua
le cua » ly cua
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: ((tu sach) OR (te sach)) ky tang xa hoi. ((hieu van) or (hieu va)) cuu thuc dan hanh le cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (te sach)) ky tang xa hoi. ((hieu van) OR (hieu va)) cuu thuc dan hanh le cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) OR (te sach)) ky tang xa hoi. ((hieu van) or (hieu va)) cuu thuc dan hanh le cua te".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) OR (te sach)) ky tang xa hoi. ((hieu van) or (hieu va)) cuu thuc dan hanh le cua te*.