Perhaps you should try some spelling variations:
va hanh » van hanh, va thanh, va danh
sach ky » sach y, sach ty, sach kem
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky
ve cac » va cac, vien cac
xuc va » duc va, tuc va, luc va
vi cua » vai cua, di cua
ve cai » va cai, ve tai, ve cau
x hoi » xa hoi, o hoi, x ho

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu ((sach ky) or (sac ky)) nang x hoi. hieu ((ve cai) or (ve cac)) xuc va hanh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang x hoi. hieu ((ve cai) OR (ve cac)) xuc va hanh vi cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang x hoi. hieu ((ve cai) or (ve cac)) xuc va hanh vi cua tre*.