Perhaps you should try some spelling variations:
cac thuat » va thuat, hoc thuat, cac thu
doanh van » doan van, doanh va, doanh ban
toc sach » hoc sach, doc sach, thuoc sach
thi hanh » thi thanh
va doanh » van doanh, vay doanh, va danh
thuat va » thuyet va, thuat xay, thuat bai
van cua » vang cua, ban cua, dan cua
cua tre » cua te, cuu tre, cua triet
thi van » thi lan, thi nang
lang xa » lang ha, dang xay, lang van
tang ma » mang may, tang van

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 ((tang ma) or (lang xa)) hoi. ((thi van) OR (thi hanh)) cac thuat va doanh van cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach y ((tang ma) OR (lang xa)) hoi. ((thi van) OR (thi hanh)) cac thuat va doanh van cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc sach y ((tang ma) or (lang xa)) hoi. ((thi van) OR (thi hanh)) cac thuat va doanh van cua tre*".