Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
truc van » truc va, thuc van, truc ban
tru nang » tra nang, tri nang, truc nano
hang vi » hang va, hanh vi, hang di
tuc van » thuc van, tuc va, duc van
va cham » va chat, va tham
hieu va » lieu va, hieu qua
tu nang » tu nong, tu nano, tu lang
cua tre » cua te, cuu tre, cua triet
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: toc sach ((tu nang) OR (tru nang)) xa hoi. hieu va cham ((tuc van) or (truc van)) hang vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((tu nang) OR (tru nang)) xa hoi. hieu va cham ((tuc van) OR (truc van)) hang vi cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ((tu nang) OR (tru nang)) xa hoi. hieu va cham ((tuc van) or (truc van)) hang vi cua tre*".