Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
van hanh » van thanh, ban hanh, van anh
lang mai » lang dai, lang hai, lang man
tu cach » tu cac
xuc van » duc van, luc van, vuc van
ve cham » va cham, ve chat, vu cham
mai hoi » mai khoi, dai hoi, lai hoi
ky lang » ky nang, ky dang, ky tang
cua tre » cua te, cuu tre, cua triet
ve cac » va cac, vien cac
vi cua » vai cua, di 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 lang mai hoi. hieu ((ve cham) or (ve cac)) xuc van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu cach) OR (thuat sach)) ky lang mai hoi. hieu ((ve cham) OR (ve cac)) xuc van hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((tu cach) or (thuat sach)) ky lang mai hoi. hieu ((ve cham) or (ve cac)) xuc van hanh vi cua tre*.