Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
van hanh » van thanh, ban hanh, van anh
vien cac » vien bach, vien dai, vien da
tu cach » tu cac
hanh va » hang va, hanh vi
luc van » luoc van, luu van, duc van
ve cham » va cham, ve chat, vu cham
tang ma » mang may, tang van
ky tang » ky nang, ky dang, kho tang
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
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: ((tu cach) or (thuat sach)) ky tang ma hoi. hieu ((ve cham) or (vien cac)) luc van hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thuat sach)) ky tang ma hoi. hieu ((ve cham) OR (vien cac)) luc van hanh va cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (thuat sach)) ky tang ma hoi. hieu ((ve cham) or (vien cac)) luc van hanh va cua tre*.