Perhaps you should try some spelling variations:
vat trong » viet trong, cay trong, dot trong
vat tang » van tang, vat mang, tat thang
cam thuc » am thuc, nam thuc, cam thu
sach ty » sach tu, sach thu, xach tay
tai cua » thai cua, tai cuc, tri cua
cua tre » cua te, cuu tre, cua triet
hieu va » lieu va, hieu qua
hang x » nang x, hoang xa, chang xu
va cam » va cham, va cac, va cao
x hoi » xa hoi, o hoi, x ho

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 ty) or (sach y)) hang x hoi. hieu va cam thuc ((vat tang) OR (vat trong)) tai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ty) OR (sach y)) hang x hoi. hieu va cam thuc ((vat tang) OR (vat trong)) tai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ty) or (sach y)) hang x hoi. hieu va cam thuc ((vat tang) OR (vat trong)) tai cua tre".
• Adding a wildcard symbol may retrieve word variants: te ((sach ty) or (sach y)) hang x hoi. hieu va cam thuc ((vat tang) OR (vat trong)) tai cua tre*.