Perhaps you should try some spelling variations:
thi nang » ki nang, thi hanh
thi cong » tai cong, thien cong
ban hanh » ban hang
van hanh » van thanh, van anh, van ban
te sach » toc sach
vai cua » dai cua, hai cua, lai cua
hieu ve » hieu va, hieu van
cac ung » cac chung, cac cong, cac dang
cho hoc » co hoc, khoa hoc
cua cau » cua cac, cua chu, cua cay
ve cac » va cac, vien cac

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