Perhaps you should try some spelling variations:
viet cac » viet ca, viet bac, viet cau
vien cac » vien bach, vien dai, vien da
bai cuu » bai cua, bai cung
anh bai » sach bai, danh bat, hinh bai
van anh » van thanh, tuan anh, van minh
tu sach » thu sach, te sach, tu cach
su sach » so sach, vu sach
cuu tre » cua tre, cau tren, cau treo
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (su sach)) ky nang x hoi. sieu ((viet cac) OR (vien cac)) vo van anh bai cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (su sach)) ky nang x hoi. sieu ((viet cac) OR (vien cac)) vo van anh bai cuu tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (su sach)) ky nang x hoi. sieu ((viet cac) OR (vien cac)) vo van anh bai cuu tre*".