Perhaps you should try some spelling variations:
qua cham » qua hai, qua cac, va cham
dien cuc » dien tu, dieu cua, vien cac
dan dien » doan dien, danh dien, dan den
te sach » toc sach
nang xa » lang xa, nang ma, mang xa
sach v » sach va, sach y, sach 2
doc va » duoc va, duc va, loc va
cuc te » cua te, cuc thue, cuc tieu

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach v ((nang xa) OR (nang x)) hoi. hieu qua cham ((hoc va) or (doc va)) dan dien cuc te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach v ((nang xa) OR (nang x)) hoi. hieu qua cham ((hoc va) OR (doc va)) dan dien cuc te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach v ((nang xa) OR (nang x)) hoi. hieu qua cham ((hoc va) or (doc va)) dan dien cuc te".
• Adding a wildcard symbol may retrieve word variants: te sach v ((nang xa) OR (nang x)) hoi. hieu qua cham ((hoc va) or (doc va)) dan dien cuc te*.