Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
hieu va » lieu va, hieu qua
duc ban » duc tan, duc van, dua ban
xuc ban » cuc ban, quoc ban, xuat ban
te sach » toc sach
nang ma » tang ma, sang ma, nang cao
ty nang » ky nang, ty xang, ty hang
ma hoi » mai hoi, xa hoi, ma hoa
va cam » va cham, va cac, va cao
vi cua » vai cua, di cua
cua su » qua su

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 (thuat sach)) ty nang ma hoi. hieu va cam ((xuc ban) OR (duc ban)) hanh vi cua su~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (thuat sach)) ty nang ma hoi. hieu va cam ((xuc ban) OR (duc ban)) hanh vi cua su.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (thuat sach)) ty nang ma hoi. hieu va cam ((xuc ban) OR (duc ban)) hanh vi cua su".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (thuat sach)) ty nang ma hoi. hieu va cam ((xuc ban) OR (duc ban)) hanh vi cua su*.