Perhaps you should try some spelling variations:
danh vien » doanh vien, danh viet, dan vien
dang xay » dang van, van xay
thu sach » tu sach, thuat sach, thuoc sach
vien cac » vien bach, vien dai, vien da
lang xa » lang van
lang ha » long ha
qua cau » quan cau, qua cac, qua ca
truc va » thuc va, thuc vat, trung va
va danh » va dinh, va dan, va hanh

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

• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y ((((lang xa) OR (lang ha))) OR (dang xay)) hoi. hieu qua cau truc va danh vien cac tro~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y ((((lang xa) OR (lang ha))) or (dang xay)) hoi. hieu qua cau truc va danh vien cac tro~".
• Adding a wildcard symbol may retrieve word variants: thu sach y ((((lang xa) OR (lang ha))) or (dang xay)) hoi. hieu qua cau truc va danh vien cac tro*.