Perhaps you should try some spelling variations:
ban thanh » ban hanh, ban hang
hieu van » hieu va, thien van, lieu va
va thanh » gia thanh, va tinh, le thanh
su sach » so sach, vu sach
ky lang » ky dang, ky tang, tay lang
van hac » van hoc, van ha, van hai
hac tuc » thac toc, thai tuc
vi cua » vai cua, di cua
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: su sach ((ky lang) OR (ky nang)) xa hoi. hieu van hac tuc ((va thanh) or (ban thanh)) vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su sach ((ky lang) OR (ky nang)) xa hoi. hieu van hac tuc ((va thanh) OR (ban thanh)) vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su sach ((ky lang) OR (ky nang)) xa hoi. hieu van hac tuc ((va thanh) or (ban thanh)) vi cua te".
• Adding a wildcard symbol may retrieve word variants: su sach ((ky lang) OR (ky nang)) xa hoi. hieu van hac tuc ((va thanh) or (ban thanh)) vi cua te*.