Perhaps you should try some spelling variations:
phau benh » kham benh
nhap quoc » han quoc, nha nuoc, phap nuoc
nay quoc » nam quoc, nhan quoc, han quoc
sach do » sach dao, sach doi, sach lo
benh vi » benh va, benh ve, benh li
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
song xa » song cua
sach de » cach de, sach dao, sach dat
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: te ((sach do) OR (sach de)) song xa hoi. hieu va ((nay quoc) or (nhap quoc)) phau benh vi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach do) OR (sach de)) song xa hoi. hieu va ((nay quoc) OR (nhap quoc)) phau benh vi cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach do) OR (sach de)) song xa hoi. hieu va ((nay quoc) or (nhap quoc)) phau benh vi cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach do) OR (sach de)) song xa hoi. hieu va ((nay quoc) or (nhap quoc)) phau benh vi cua tre*.