Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
hieu va » lieu va, hieu qua
cac ban » cac dan, cac van, can ban
van dat » van dao, van dau, dan dat
cua tre » cua te, cua triet, dua tren
cuu tre » cau tren, cau treo
tu sac » tu sach, tu cac, tu san

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sac) or (thu sach)) ky tang xa hoi. hieu va cac ban va van dat ((cua tre) OR (cuu tre))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sac) OR (thu sach)) ky tang xa hoi. hieu va cac ban va van dat ((cua tre) OR (cuu tre)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sac) or (thu sach)) ky tang xa hoi. hieu va cac ban va van dat ((cua tre) OR (cuu tre))".
• Adding a wildcard symbol may retrieve word variants: ((tu sac) or (thu sach)) ky tang xa hoi. hieu va cac ban va van dat ((cua tre) OR (cuu tre))*.