Perhaps you should try some spelling variations:
thu sach » tu sach, thuat sach, thuoc sach
viec lam » viec va
vien cac » vien bach, vien da, gian cac
vien dai » hien dai
cao hoa » cao hoat, cao khoa, cau hoa
va hang » van hang, va nang, va lang
cua tre » cua te, cuu tre, cua triet
y nang » ky nang, ly nang, v nang
va cua » va chua, via cua, ca cua

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 y nang cao hoa. hieu ((viec lam) or (((vien cac) OR (vien dai)))) tu va hang va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach y nang cao hoa. hieu ((viec lam) OR (((vien cac) OR (vien dai)))) tu va hang va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach y nang cao hoa. hieu ((viec lam) or (((vien cac) OR (vien dai)))) tu va hang va cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach y nang cao hoa. hieu ((viec lam) or (((vien cac) OR (vien dai)))) tu va hang va cua tre*.