Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
sach ky » sac ky, sach y, sach ty
cuu tre » cua tre, cau treo
danh vi » hanh vi, dinh vi, danh di
va danh » va dinh, va dan, va hanh
te sach » toc sach
hieu va » hieu qua
lang xa » lang ha, dang xay, lang van
ky lang » ky nang, ky dang, ky tang
soc va » hoc va, loc va, doc va

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 ky lang xa hoi. ((hieu va) or (lieu va)) cham soc va danh vi ((cuu tre) OR (cau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky lang xa hoi. ((hieu va) OR (lieu va)) cham soc va danh vi ((cuu tre) OR (cau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky lang xa hoi. ((hieu va) or (lieu va)) cham soc va danh vi ((cuu tre) OR (cau tren))".
• Adding a wildcard symbol may retrieve word variants: te sach ky lang xa hoi. ((hieu va) or (lieu va)) cham soc va danh vi ((cuu tre) OR (cau tren))*.