Perhaps you should try some spelling variations:
thai va » thai van
va tinh » may tinh
sach ky » sac ky, sach y, sach ty
so sach » so sanh, bo sach, co sach
nam xuc » cam xuc, nam xua, nam thuc
hieu va » lieu va, hieu qua
nang ma » tang ma, sang ma, nang cao
va nam » van nam, ha nam, va nay
ma hoi » mai hoi, xa hoi, ma hoa
hai va » hai van, hoi 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: so sach ky nang ma hoi. hieu va nam xuc ((gia thanh) or (va tinh)) ((hai va) OR (thai va)) triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach ky nang ma hoi. hieu va nam xuc ((gia thanh) OR (va tinh)) ((hai va) OR (thai va)) triet*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ky nang ma hoi. hieu va nam xuc ((gia thanh) or (va tinh)) ((hai va) OR (thai va)) triet*".