Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
ban hanh » ban hang
hieu van » hieu va, thien van, lieu va
tru nang » tra nang, tri nang, truc nano
cau treo » cau theo, cau tren, cau triet
tu nano » truc nano
van cam » van nam, van lam, van cau
xuc ban » duc ban, cuc ban, quoc ban
tu nang » tu nong, tu lang, vu nang
vi cau » va cau, ve cau, di cau

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 (tu nano))) or (tru nang)) xa hoi. hieu van cam xuc ban hanh vi cau treo~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ((((tu nang) OR (tu nano))) OR (tru nang)) xa hoi. hieu van cam xuc ban hanh vi cau treo.
• Adding a wildcard symbol may retrieve word variants: toc sach ((((tu nang) or (tu nano))) or (tru nang)) xa hoi. hieu van cam xuc ban hanh vi cau treo*.