Perhaps you should try some spelling variations:
danh vai » danh sai, danh va, doanh van
qua cham » qua hai, qua cac, va cham
vai cua » dai cua, hai cua, lai cua
sach ty » sach y, sach tu, sach thu
vu sach » vu bach, su sach, vu khach
lang xa » lang ha, dang xay, lang van
cua tre » cua te, cuu tre, cua triet
xuc va » duc va, luc va, xac va
tuc va » thuc va, truc va, tuc xa

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 ty ((lang xa) or (nang cao)) hoi. hieu qua cham ((xuc va) OR (tuc va)) danh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: vu sach ty ((lang xa) OR (nang cao)) hoi. hieu qua cham ((xuc va) OR (tuc va)) danh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "vu sach ty ((lang xa) or (nang cao)) hoi. hieu qua cham ((xuc va) OR (tuc va)) danh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: vu sach ty ((lang xa) or (nang cao)) hoi. hieu qua cham ((xuc va) OR (tuc va)) danh vai cua tre*.