Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
dau vien » dau tien, dan vien, dau bien
vien cac » vien bach, vien dai, vien da
ky lang » ky nang, ky tang, tay lang
ky dang » ky nang, ky danh
qua cau » quan cau, qua cac, qua ca
truc va » thuc va, thuc vat, trung va
va dau » va dao

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((ky lang) or (ky dang)) xa hoi. hieu qua cau truc va dau vien cac tro~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((ky lang) OR (ky dang)) xa hoi. hieu qua cau truc va dau vien cac tro.
• Adding a wildcard symbol may retrieve word variants: thu sach ((ky lang) or (ky dang)) xa hoi. hieu qua cau truc va dau vien cac tro*.