Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
hieu van » hieu va, thien van, lieu va
sach ky » sac ky, sach y, sach ty
cuu tre » cua tre, cau treo
te sach » toc sach
nam xuc » cam xuc, nam xua, nam thuc
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
va dan » va dao, va dau, va dap
ca dan » cac dan, ca dao

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