Perhaps you should try some spelling variations:
cac quoc » cac nuoc, cac cuoc, cao quoc
thai cua » than cua, tai cuc, tri cua
lan vanh » lan anh, lan oanh, lan van
quoc lan » quoc ban, nuoc luan, quoc quan
te sach » toc sach
tai cua » tai cuc, tri cua, dai cua
qua cac » cua cac
nang xa » nang x, lang xa, mang xa
nang ma » tang ma, sang ma, nang cao

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 y ((nang xa) or (nang ma)) hoi. hieu qua cac quoc lan vanh ((tai cua) OR (thai cua)) tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach y ((nang xa) OR (nang ma)) hoi. hieu qua cac quoc lan vanh ((tai cua) OR (thai cua)) tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach y ((nang xa) or (nang ma)) hoi. hieu qua cac quoc lan vanh ((tai cua) OR (thai cua)) tre".
• Adding a wildcard symbol may retrieve word variants: te sach y ((nang xa) or (nang ma)) hoi. hieu qua cac quoc lan vanh ((tai cua) OR (thai cua)) tre*.