Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
van hanh » van thanh, ban hanh, van anh
hanh ket » thanh ket, hanh kem, doanh ket
sach ky » sac ky, sach y, sach ty
nang xa » nang x, lang xa, nang ma
hieu va » hieu qua
cam duc » cam xuc, cao duc, pham duc
duc van » duc va, duc tan, duc manh
ket hoa » ket hop

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ky nang xa hoi. ((lieu va) or (hieu va)) cam duc van hanh ket hoa viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ky nang xa hoi. ((lieu va) OR (hieu va)) cam duc van hanh ket hoa viet.
• Adding a wildcard symbol may retrieve word variants: toc sach ky nang xa hoi. ((lieu va) or (hieu va)) cam duc van hanh ket hoa viet*.