Perhaps you should try some spelling variations:
qua cham » qua hai, qua cac, va cham
truc va » thuc va, thuc vat, trung va
vu sach » vu bach, su sach, vu khach
lang xa » lang ha, dang xay, lang van
nang ma » tang ma, sang ma, nang cao
cua tre » cua te, cuu tre, cua triet
tuc va » thuc va, tuc xa, duc va
vi cua » vai cua, di cua

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