Perhaps you should try some spelling variations:
cau tren » cu tren, dau tren, ca tren
te sach » toc sach
sach ky » sac ky, sach y, sach ty
hieu ve » hieu va, hieu van
cac duc » cac du, cao duc, cac dac
va tinh » may tinh
tinh vi » trinh vi, tinh voi, tinh va
cuu tre » cua tre, cau treo
ve cac » va cac, vien cac

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: te sach ky nang x ho. hieu ve cac duc va tinh vi ((cuu tre) OR (cau tren))~.
• Adding a wildcard symbol may retrieve word variants: te sach ky nang x ho. hieu ve cac duc va tinh vi ((cuu tre) or (cau tren))*.