Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
thanh va » thanh van, hanh va, thanh ha
van pham » san pham, van phan, van phat
hieu van » hieu va, thien van, lieu va
vu sach » vu bach, vu khach
duc ban » duc tan, duc van, dua ban
cuu tre » cua tre, cau tren, cau treo
nang ma » tang ma, sang ma, nang cao
nang xa » nang x, lang xa, mang xa
su sach » so sach
va cuu » va cau, va chu, va huu

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((vu sach) OR (su sach)) ky ((nang xa) or (nang ma)) hoi. hieu van pham duc ban thanh va cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((vu sach) OR (su sach)) ky ((nang xa) OR (nang ma)) hoi. hieu van pham duc ban thanh va cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((vu sach) OR (su sach)) ky ((nang xa) or (nang ma)) hoi. hieu van pham duc ban thanh va cuu tre".
• Adding a wildcard symbol may retrieve word variants: ((vu sach) OR (su sach)) ky ((nang xa) or (nang ma)) hoi. hieu van pham duc ban thanh va cuu tre*.