Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van hanh » van thanh, ban hanh, van anh
te sach » toc sach
sach ty » sach y, sach tu, sach thu
van hac » van hoc, van ha, van hai
cua tre » cua te, cuu tre, cua triet
xang o » lang o, tang o, dang o
hac so » hai so, ham so, hoc so
so van » su van, vo van
vi cua » vai cua, di cua
o hai » co hai, so hai, o lai

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ty xang o hai. hieu van hac so van hanh vi cua tre~.
• Adding a wildcard symbol may retrieve word variants: te sach ty xang o hai. hieu van hac so van hanh vi cua tre*.