Perhaps you should try some spelling variations:
thien van » thi van
nham thuc » nhan thuc, nam thuc, nham thu
sinh dai » sinh thai, si dai, sinh vat
cham tuc » pham thuc, tham thuc, cham soc
toc sach » hoc sach, doc sach, thuoc sach
nang ma » tang ma, sang ma, nang cao
sach ty » sach y, sach tu, sach thu
nang xa » nang x, lang xa, mang xa
va sinh » va kinh, va tinh, vi sinh
cua tre » cua te, cuu tre, cua triet

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: toc sach ty ((nang xa) or (nang ma)) hoi. thien van ((cham tuc) or (nham thuc)) va sinh dai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: toc sach ty ((nang xa) OR (nang ma)) hoi. thien van ((cham tuc) OR (nham thuc)) va sinh dai cua tre.
• Adding a wildcard symbol may retrieve word variants: toc sach ty ((nang xa) or (nang ma)) hoi. thien van ((cham tuc) or (nham thuc)) va sinh dai cua tre*.