Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh lap » thanh san, phan lap, thanh hai
sang tao » hang tai
dua tren » dung tren
hieu van » hieu va, thien van, lieu va
van cham » van chat, van tham, va cham
cham cac » cho cac, cham soc, cua cac
tu sach » thu sach, su sach, te sach
cuu tre » cua tre, cau tren, cau treo
cac ban » cac dan, cac van, can ban
sach ty » sach y, sach tu, sach thu
tao hoi » tao khoi, tao boi, tay hoi
ty sang » ty xang, ty hang, duy sang
cua te » cua tu

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 ty sang tao hoi. hieu van cham cac ban thanh lap ((((dua tren) or (cuu tre))) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ty sang tao hoi. hieu van cham cac ban thanh lap ((((dua tren) OR (cuu tre))) OR (cua te)).
• Adding a wildcard symbol may retrieve word variants: tu sach ty sang tao hoi. hieu van cham cac ban thanh lap ((((dua tren) or (cuu tre))) or (cua te))*.