Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
qua cham » qua hai, qua cac, va cham
hanh doi » thanh doi, hanh noi, hang doi
cau tren » cu tren, dau tren, ca tren
su sach » so sach, vu sach
sach ky » sac ky, sach y, sach ty
soc van » hoc van, oc van, sac van
doi cau » doi dau, di cau, doi ca
5 hoi » o hoi

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: su sach ky nang ((5 hoi) OR (x ho)). hieu qua cham soc van hanh doi cau tren~.
• Adding a wildcard symbol may retrieve word variants: su sach ky nang ((5 hoi) or (x ho)). hieu qua cham soc van hanh doi cau tren*.