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

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) OR (thuoc sach)) y nang xa 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) OR (thuoc sach)) y nang xa 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) OR (thuoc sach)) y nang xa hoi. hieu van hau loc van thanh de ((cuu tre) or (tu tieng))".
• Adding a wildcard symbol may retrieve word variants: ((toc sach) OR (thuoc sach)) y nang xa hoi. hieu van hau loc van thanh de ((cuu tre) or (tu tieng))*.