Perhaps you should try some spelling variations:
te sach » toc sach
tai cua » thai cua, tai cuc, tri cua
han tai » hang tai, nhan tai, van tai
hieu va » lieu va, hieu qua
cua tre » cua te, cuu tre, cua triet
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang
luc va » duc va, loc va
tuc va » thuc va, truc va, tuc xa
tu san » thu san, tu ban, tu can
va cam » va cham, va cac, va cao

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 (tu san)) ky tang xa hoi. hieu va cam ((luc va) OR (tuc va)) han tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (tu san)) ky tang xa hoi. hieu va cam ((luc va) OR (tuc va)) han tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (tu san)) ky tang xa hoi. hieu va cam ((luc va) OR (tuc va)) han tai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (tu san)) ky tang xa hoi. hieu va cam ((luc va) OR (tuc va)) han tai cua tre*.