Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, hieu ve
dau thau » dau tu
thau cuu » thai cua, than cua, thau dau
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
nang xa » nang x, lang xa, nang ma
cuu tre » cua tre, cau tren, cau treo
y nang » ky nang, ly nang, v nang
va dau » va dao
nuoc » quoc, duoc, ngoc

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 (su sach)) y nang xa hoi. ((hieu van) or (lieu va)) dat nuoc va dau thau cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) y nang xa hoi. ((hieu van) OR (lieu va)) dat nuoc va dau thau cuu tre.
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (su sach)) y nang xa hoi. ((hieu van) or (lieu va)) dat nuoc va dau thau cuu tre*.