Perhaps you should try some spelling variations:
thanh lai » thanh hai, thanh lap, thanh loi
ban thanh » ban hanh, ban hang
cua viet » ca viet, hoa viet, cua vat
hieu van » hieu va, thien van, lieu va
lai cua » dai cua, hai cua, lai chau
dua ban » dia ban, cua ban, qua ban
nam dua » nam da, nam cua, nam mua
sach ky » sach y, sach ty, sach kem
nang xa » lang xa, nang ma, mang xa
sac ky » cac ky, sai ky

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 ky) OR (sac ky)) ((nang xa) or (nang x)) hoi. hieu van nam dua ban thanh lai cua viet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) ((nang xa) OR (nang x)) hoi. hieu van nam dua ban thanh lai cua viet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sac ky)) ((nang xa) or (nang x)) hoi. hieu van nam dua ban thanh lai cua viet".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) OR (sac ky)) ((nang xa) or (nang x)) hoi. hieu van nam dua ban thanh lai cua viet*.