Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
kham soc » cham soc, kham cuoc, ham so
sach ty » sach tu, sach thu, xach tay
soc van » hoc van, oc van, sac van
vu kham » vu khanh
hieu vu » hieu va, hieu ve, hieu su
cua tre » cua te, cuu tre, cua triet
lang ha » long ha
nang xa » nang x, lang xa, nang ma
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: so ((sach ty) OR (sach y)) ((nang xa) or (lang ha)) hoi. hieu vu kham soc van hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so ((sach ty) OR (sach y)) ((nang xa) OR (lang ha)) hoi. hieu vu kham soc van hanh vi cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so ((sach ty) OR (sach y)) ((nang xa) or (lang ha)) hoi. hieu vu kham soc van hanh vi cua tre*".