Perhaps you should try some spelling variations:
hieu hien » bieu hien, dieu hien, chieu chien
vu khach » vu khanh, vu khac, vay khach
dinh vai » dinh van, dinh vi, dinh va
hien cac » thien cac, vien cac, hieu cac
vu sach » vu bach, su sach
vai cua » dai cua, hai cua, lai cua
va dinh » van dinh, va kinh, va tinh
cua tre » cua te, cuu tre, cua triet
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao
cac bo » bac bo, cac co
bo va » bao va, do va, so va

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((vu sach) OR (vu khach)) ky ((nang xa) or (nang ma)) hoi. hieu hien cac bo va dinh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (vu khach)) ky ((nang xa) OR (nang ma)) hoi. hieu hien cac bo va dinh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu sach) OR (vu khach)) ky ((nang xa) or (nang ma)) hoi. hieu hien cac bo va dinh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: ((vu sach) OR (vu khach)) ky ((nang xa) or (nang ma)) hoi. hieu hien cac bo va dinh vai cua tre*.