Perhaps you should try some spelling variations:
kham truc » nham thuc, pham thuc, kham trai
te sach » toc sach
day cua » dai cua
dan day » da day, dan dat, dan da
truc va » thuc va, thuc vat, trung va
cua tre » cua te, cuu tre, cua triet
sach ky » sac ky, sach y, sach ty
hieu va » lieu va
nang ma » tang ma, sang ma, mang may
va dan » ca dan, va dao, va dau

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 ky ((nang ma) OR (nang cao)) hoi. ((hieu va) or (hieu qua)) kham truc va dan day cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky ((nang ma) OR (nang cao)) hoi. ((hieu va) OR (hieu qua)) kham truc va dan day cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky ((nang ma) OR (nang cao)) hoi. ((hieu va) or (hieu qua)) kham truc va dan day cua tre*".