Perhaps you should try some spelling variations:
van hanh » van thanh, ban hanh, van anh
thi hang » thi hanh, thi nang, thi hong
te sach » toc sach
duc van » duc va, duc tan, duc manh
coc duc » hoc duc, coc luc, hoc duoc
hieu ve » hieu va, hieu van
cua cau » cua cac, cua chu, cua cay
cho hoc » khoa hoc
ty hang » ly hang, ty xang, thu hang
ve coc » ve cuoc, ve cac, ve co
vi cua » vai cua, di cua

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 ((ty hang) OR (thi hang)) ((cho hoc) or (co hoc)). hieu ve coc duc van hanh vi cua cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((ty hang) OR (thi hang)) ((cho hoc) OR (co hoc)). hieu ve coc duc van hanh vi cua cau*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((ty hang) OR (thi hang)) ((cho hoc) or (co hoc)). hieu ve coc duc van hanh vi cua cau*".