Perhaps you should try some spelling variations:
hanh va » hanh vi
duc ton » duc tan
cac duc » cac du, cao duc, cac dac
sach ky » sac ky, sach y, sach kem
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van
nang xa » nang x, lang xa, nang ma
sach ty » sach y, sach tu, sach thu
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: toc ((sach ky) or (sach ty)) nang xa hoi. hieu ve cac duc ton ((hanh va) OR (hang va)) cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc ((sach ky) OR (sach ty)) nang xa hoi. hieu ve cac duc ton ((hanh va) OR (hang va)) cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "toc ((sach ky) or (sach ty)) nang xa hoi. hieu ve cac duc ton ((hanh va) OR (hang va)) cua tre".
• Adding a wildcard symbol may retrieve word variants: toc ((sach ky) or (sach ty)) nang xa hoi. hieu ve cac duc ton ((hanh va) OR (hang va)) cua tre*.