Perhaps you should try some spelling variations:
hieu van » thien van, lieu va, hieu ve
cac quoc » cac nuoc, cac cuoc, cao quoc
quoc ban » quoc bao, quoc lan, quoc quan
ban benh » san benh, ba benh, ban banh
sach ky » sac ky, sach ty, sach kem
nang xa » nang x, lang xa, nang ma
hieu va » lieu va, hieu qua
benh vi » benh va, benh ve, benh li
cua tre » cua te, cuu tre, cua triet
vi cua » vai cua, di cua

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) OR (sach y)) nang xa hoi. ((hieu van) or (hieu va)) cac quoc ban benh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sach y)) nang xa hoi. ((hieu van) OR (hieu va)) cac quoc ban benh vi cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) OR (sach y)) nang xa hoi. ((hieu van) or (hieu va)) cac quoc ban benh vi cua tre*".