Perhaps you should try some spelling variations:
van hanh » van thanh, van anh, van ban
dieu cua » dieu tra
ban hanh » ban hang
cua tre » cua te, cuu tre, cua triet
trai ky » thai ky
nang xa » nang x, lang xa, nang ma
hieu ve » hieu va, hieu van
cau duc » cao duc, cau luc, chu duc
dai ky » dan ky, dai ly, sai ky
ve cau » ke cau, va cau, ve 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 ((dai ky) or (trai ky)) nang xa hoi. hieu ve cau duc ((van hanh) OR (ban hanh)) dieu cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((dai ky) OR (trai ky)) nang xa hoi. hieu ve cau duc ((van hanh) OR (ban hanh)) dieu cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((dai ky) or (trai ky)) nang xa hoi. hieu ve cau duc ((van hanh) OR (ban hanh)) dieu cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((dai ky) or (trai ky)) nang xa hoi. hieu ve cau duc ((van hanh) OR (ban hanh)) dieu cua tre*.