Perhaps you should try some spelling variations:
cham loc » cham soc, chon loc, cham o
hieu van » thien van, lieu va, hieu ve
sach ky » sac ky, sach y, sach ty
vai cua » dai cua, hai cua, lai cua
va danh » va dinh, va hanh, dia danh
tu sach » thu sach, su sach, te sach
hieu va » lieu va, hieu qua
dang xa » dang xay, lang xa, dang ha
ky dang » ky nang, ky danh
cua tre » cua te, cuu tre, cua triet
va dan » ca dan, va dao, va dau

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 dang xa hoi. ((hieu van) OR (hieu va)) cham loc ((va danh) or (va dan)) vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky dang xa hoi. ((hieu van) OR (hieu va)) cham loc ((va danh) OR (va dan)) vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky dang xa hoi. ((hieu van) OR (hieu va)) cham loc ((va danh) or (va dan)) vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky dang xa hoi. ((hieu van) OR (hieu va)) cham loc ((va danh) or (va dan)) vai cua tre*.