Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
toc sach » hoc sach, doc sach, thuoc sach
thanh de » hanh de, thanh ve, thanh do
hieu van » hieu va, thien van, lieu va
tu tieng » luc tieng, tu tuong, tu trong
van hau » van ha, van hai, van dau
loc van » luoc van, hoc van, lo van
nang xa » lang xa, nang ma, mang xa
cuu tre » cua tre, cau tren, cau treo
hau loc » huu loc, phau hoc

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

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach y ((nang xa) OR (nang x)) hoi. hieu van hau loc van thanh de ((cuu tre) or (tu tieng))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y ((nang xa) OR (nang x)) hoi. hieu van hau loc van thanh de ((cuu tre) OR (tu tieng)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y ((nang xa) OR (nang x)) hoi. hieu van hau loc van thanh de ((cuu tre) or (tu tieng))".
• Adding a wildcard symbol may retrieve word variants: toc sach y ((nang xa) OR (nang x)) hoi. hieu van hau loc van thanh de ((cuu tre) or (tu tieng))*.