Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
te sach » toc sach
san cua » sang cua, ban cua, dan cua
tac van » tac vang, cac van, tac va
cac tac » cac toc, cac bac, cac dac
hieu va » lieu va, hieu qua
sach ky » sac ky, sach y, sach ty
hieu ve » hieu van
hoa hoi » khoa hoi, hoa hoc, hoa doi
ky dang » ky nang, ky danh
cua tre » cua te, cuu tre, cua triet
ha hoi » ha noi, xa hoi, va hoi

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

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky dang ((ha hoi) OR (hoa hoi)). ((hieu ve) or (hieu va)) cac tac van thanh san cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky dang ((ha hoi) OR (hoa hoi)). ((hieu ve) OR (hieu va)) cac tac van thanh san cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky dang ((ha hoi) OR (hoa hoi)). ((hieu ve) or (hieu va)) cac tac van thanh san cua tre*".