Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
te sach » toc sach
van anh » van thanh, tuan anh, van minh
luc van » luoc van, luu van, duc van
nam luc » nang luc, nhan luc, nam thuc
hieu va » lieu va, hieu qua
sach ly » sach y, sach lo, sach ty
cua tre » cua te, cuu tre, cua triet
cao hoc » co hoc, cho hoc, chat hoc
cao hoi » cau hoi, co hoi, tao hoi
ly nang » ky nang, ly hang, ly vang
anh vi » hanh vi, anh va, anh ve
vi cua » vai cua, di cua

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ly nang ((cao hoi) or (cao hoc)). ((hieu van) OR (hieu va)) nam luc van anh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ly nang ((cao hoi) OR (cao hoc)). ((hieu van) OR (hieu va)) nam luc van anh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ly nang ((cao hoi) or (cao hoc)). ((hieu van) OR (hieu va)) nam luc van anh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te sach ly nang ((cao hoi) or (cao hoc)). ((hieu van) OR (hieu va)) nam luc van anh vi cua tre*.