Perhaps you should try some spelling variations:
vien cac » vien bach, vien dai, vien da
van hanh » van thanh, ban hanh, van anh
nang xa » nang x, lang xa, nang ma
luu van » cuu van, luan van, luu hanh
cua tre » cua te, cuu tre, cua triet
te dai » tre dai, te tai, he dai
dai ky » dan ky, dai ly, sai ky
ve cac » va 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: te dai ky nang xa hoi. hieu ((ve cac) OR (vien cac)) luu van hanh vi cua tre~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te dai ky nang xa hoi. hieu ((ve cac) OR (vien cac)) luu van hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te dai ky nang xa hoi. hieu ((ve cac) OR (vien cac)) luu van hanh vi cua tre*.