Perhaps you should try some spelling variations:
vien cac » vien bach, vien da, gian cac
vien dai » hien dai
dang van » hoang van, hang va
va hanh » van hanh, va thanh, va danh
cua tre » cua te, cuu tre, cua triet
nang xa » nang x, lang xa, nang ma
sac ky » cac ky, sai ky
loc va » hoc va, luc va
vi cua » vai cua, di cua
te sac » te sach, te cac, te san

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sac ky ((nang xa) or (dang van)) hoi. hieu ((vien cac) OR (vien dai)) loc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sac ky ((nang xa) OR (dang van)) hoi. hieu ((vien cac) OR (vien dai)) loc va hanh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sac ky ((nang xa) or (dang van)) hoi. hieu ((vien cac) OR (vien dai)) loc va hanh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te sac ky ((nang xa) or (dang van)) hoi. hieu ((vien cac) OR (vien dai)) loc va hanh vi cua tre*.