Perhaps you should try some spelling variations:
van thanh » ban thanh, van tuan
van hanh » ban hanh, van anh, van ban
tu sach » thu sach, su sach, te sach
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
ve cam » ve cham, va cam, ve cai
vi cua » vai cua, di cua
ve cac » va cac, vien cac
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 ky nang x hoi. hieu ((ve cam) or (ve cac)) luu ((van hanh) OR (van thanh)) vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach ky nang x hoi. hieu ((ve cam) OR (ve cac)) luu ((van hanh) OR (van thanh)) vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach ky nang x hoi. hieu ((ve cam) or (ve cac)) luu ((van hanh) OR (van thanh)) vi cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach ky nang x hoi. hieu ((ve cam) or (ve cac)) luu ((van hanh) OR (van thanh)) vi cua tre*.