Perhaps you should try some spelling variations:
cua triet » cua viet, su triet, va triet
chet duoc » che duoc, cho duoc, che quoc
toc sach » hoc sach, doc sach, thuoc sach
chat duc » chat xuc, chat doc, pham duc
hieu va » lieu va, hieu qua
nang xa » nang x, lang xa, nang ma
v nang » va nang, vu nang, van nang
va dan » ca dan, va dao, va dau
dan vi » doan vi, don vi, dan va
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) or (toc sach)) v nang xa hoi. hieu va ((chat duc) OR (chet duoc)) va dan vi cua triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) v nang xa hoi. hieu va ((chat duc) OR (chet duoc)) va dan vi cua triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (toc sach)) v nang xa hoi. hieu va ((chat duc) OR (chet duoc)) va dan vi cua triet".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) v nang xa hoi. hieu va ((chat duc) OR (chet duoc)) va dan vi cua triet*.