Perhaps you should try some spelling variations:
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cuu tre » cau tren, cau treo
va hanh » van hanh, va thanh, va danh
cau luc » cau truc, cau phuc
cua tre » cua te, cua triet, dua tren
cam luc » cam xuc
hieu va » lieu va, hieu qua
tang xa » trang xa, tang ma, lang xa
ky tang » ky nang, ky dang, kho tang

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

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