Perhaps you should try some spelling variations:
va hanh » van hanh, va thanh, va danh
tu sach » thu sach, su sach, te sach
du hanh » dieu hanh, duy khanh, luu hanh
tu hang » thu hang, tu hanh, tu hung
co hoi » co hoc, co loi
ve cai » va cai, ve cac, ve tai
vi cua » vai cua, di cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach ((tu hang) or (du hanh)) co hoi. hieu ((ve cai) or (va cac)) duc va hanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ((tu hang) OR (du hanh)) co hoi. hieu ((ve cai) OR (va cac)) duc va hanh vi cua te.
• Adding a wildcard symbol may retrieve word variants: tu sach ((tu hang) or (du hanh)) co hoi. hieu ((ve cai) or (va cac)) duc va hanh vi cua te*.