Perhaps you should try some spelling variations:
toc sach » hoc sach, doc sach, thuoc sach
luoc gia » luc gia, luong gia, nuoc giai
thanh ve » hanh ve, thanh va, thanh vien
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang xa » nang x, lang xa, nang ma
hieu ve » hieu van
hieu va » lieu va, hieu qua
cuu tre » cua tre, cau tren, cau treo
ve cuu » ve cau, ve chu, ve cua

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 ty nang xa hoi. ((hieu ve) or (hieu va)) cam ((luoc gia) OR (quoc gia)) thanh ve cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty nang xa hoi. ((hieu ve) OR (hieu va)) cam ((luoc gia) OR (quoc gia)) thanh ve cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach ty nang xa hoi. ((hieu ve) or (hieu va)) cam ((luoc gia) OR (quoc gia)) thanh ve cuu tre".
• Adding a wildcard symbol may retrieve word variants: toc sach ty nang xa hoi. ((hieu ve) or (hieu va)) cam ((luoc gia) OR (quoc gia)) thanh ve cuu tre*.