Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
hanh doi » thanh doi, hanh noi, hang doi
thuc day » thuc dan
doi cua » dai cua, hoi cua
sach ky » sac ky, sach y, sach ty
hieu va » lieu va, hieu qua
hieu ve » hieu van
cao hoi » cau hoi, co hoi, cao hoc
cua te » cua tu

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 cao hoi. ((hieu ve) or (hieu va)) pham ((thuc day) or (thuc vat)) hanh doi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ky nang cao hoi. ((hieu ve) OR (hieu va)) pham ((thuc day) OR (thuc vat)) hanh doi cua te.
• Adding a wildcard symbol may retrieve word variants: thu sach ky nang cao hoi. ((hieu ve) or (hieu va)) pham ((thuc day) or (thuc vat)) hanh doi cua te*.