Perhaps you should try some spelling variations:
thanh van » thanh san, thanh toan, thanh phan
thu sach » tu sach, thuat sach, thuoc sach
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
van cua » vang cua, ban cua, dan cua
cua tre » cua te, cuu tre, cua triet
ma hoi » mai hoi, xa hoi, ma hoa
7 tang » 6 tang
y tang » ky tang, 6 tang, 5 tang
cam lo » nam lo, cam ly, cam o

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

• Performing a fuzzy search may retrieve terms with similar spellings: thu sach ((y tang) OR (7 tang)) ma hoi. hieu van ((cham h'roi) or (cam lo)) va thanh van cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: thu sach ((y tang) OR (7 tang)) ma hoi. hieu van ((cham h'roi) OR (cam lo)) va thanh van cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thu sach ((y tang) OR (7 tang)) ma hoi. hieu van ((cham h'roi) or (cam lo)) va thanh van cua tre".
• Adding a wildcard symbol may retrieve word variants: thu sach ((y tang) OR (7 tang)) ma hoi. hieu van ((cham h'roi) or (cam lo)) va thanh van cua tre*.