Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
thien van » thi van
thu sach » tu sach, thuat sach, thuoc sach
hieu van » hieu va, lieu va
va thanh » gia thanh, ban thanh, va tinh
sach ky » sac ky, sach y, sach ty
nang ma » tang ma, sang ma, nang cao
hieu ve » hieu va
hac dat » hoc dat, tac dat, hoach dat
ma hoi » mai hoi, xa hoi, ma hoa

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ky nang ma hoi. ((((hieu van) OR (hieu ve))) or (thien van)) hac dat va thanh dai cua vat~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang ma hoi. ((((hieu van) OR (hieu ve))) OR (thien van)) hac dat va thanh dai cua vat.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ky nang ma hoi. ((((hieu van) OR (hieu ve))) or (thien van)) hac dat va thanh dai cua vat".
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang ma hoi. ((((hieu van) OR (hieu ve))) or (thien van)) hac dat va thanh dai cua vat*.