Perhaps you should try some spelling variations:
benh viem » benh vien, benh ve
quoc quan » qua quan, luc quan, hoc quan
viem cua » viec cua, diem cua, nhiem cua
hieu van » hieu va, thien van, lieu va
xuc san » xuc ban, luc sang, nuoc san
van cau » van dau, van hau, van chat
sach ty » sach y, sach tu, sach thu
cao hoa » cao hoat, cao khoa, cau hoa
cua tre » cua te, cuu tre, cua triet
sac ky » cac ky, sai ky

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 ty) or (sac ky)) nang cao hoa. hieu van cau ((xuc san) or (quoc quan)) benh viem cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sac ky)) nang cao hoa. hieu van cau ((xuc san) OR (quoc quan)) benh viem cua tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ty) or (sac ky)) nang cao hoa. hieu van cau ((xuc san) or (quoc quan)) benh viem cua tre*.