Perhaps you should try some spelling variations:
va thanh » gia thanh, ban thanh, va tinh
su sach » so sach, vu sach
va hanh » van hanh, va danh, ban hanh
ky tang » ky nang, ky dang, kho tang
tang xa » trang xa, tang ma, lang xa
cau duc » cao duc, chu duc, cau truc
sach ky » sac ky, sach y, sach ty
cau luc » cau truc, cau phuc
vai va » mai va, dai va, hai va
thiet » thieu

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

• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ky tang xa hoi. hieu qua ((cau duc) OR (cau luc)) ((va hanh) OR (va thanh)) vai va thiet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ky tang xa hoi. hieu qua ((cau duc) or (cau luc)) ((va hanh) OR (va thanh)) vai va thiet~".
• Adding a wildcard symbol may retrieve word variants: su sach ky tang xa hoi. hieu qua ((cau duc) or (cau luc)) ((va hanh) OR (va thanh)) vai va thiet*.