Perhaps you should try some spelling variations:
nang tai » hang tai, tang tai, sang tai
va thanh » gia thanh, ban thanh, va tinh
tu sach » thu sach, su sach, te sach
sach ky » sac ky, sach y, sach ty
cam duc » cam xuc, cao duc, pham duc
hieu va » lieu va, hieu qua
hieu ve » hieu van
tai hai » thi hai, dai hai, tai ha
vai va » mai va, hai va, lai va
dai va » mai va

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 nang tai hai. ((hieu ve) OR (hieu va)) cam duc va thanh ((vai va) or (dai va)) hieu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang tai hai. ((hieu ve) OR (hieu va)) cam duc va thanh ((vai va) OR (dai va)) hieu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang tai hai. ((hieu ve) OR (hieu va)) cam duc va thanh ((vai va) or (dai va)) hieu".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang tai hai. ((hieu ve) OR (hieu va)) cam duc va thanh ((vai va) or (dai va)) hieu*.