Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
thanh vi » hanh vi, thanh va, thanh ve
tu sach » thu sach, su sach, te sach
duc van » duc va, duc tan, duc manh
vi cua » vai cua, di cua
cua te » cua tu
ve cac » va cac, vien cac
ve cam » ve cham, va cam, ve cai
x hoi » xa hoi, o hoi, x ho

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) or (thu hoach)) ky nang x hoi. hieu ((ve cam) OR (ve cac)) duc van thanh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu hoach)) ky nang x hoi. hieu ((ve cam) OR (ve cac)) duc van thanh vi cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu hoach)) ky nang x hoi. hieu ((ve cam) OR (ve cac)) duc van thanh vi cua te".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu hoach)) ky nang x hoi. hieu ((ve cam) OR (ve cac)) duc van thanh vi cua te*.