Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
doc sach » hoc sach, toc sach, nuoc sach
hanh doi » thanh doi, hanh noi, hang doi
van hanh » van thanh, ban hanh, van anh
dang xay » dang van, van xay
thuc van » thuc vat, thuc dan, thuc va
te sach » toc sach
doi cua » dai cua, hoi cua
ve tham » va tham, ve cham, vi tham
cua tre » cua te, cuu tre, cua triet
hieu ve » hieu va, hieu van

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) or (doc sach)) ly ((dang xay) or (nang x)) hoi. hieu ve tham thuc van hanh doi cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (doc sach)) ly ((dang xay) OR (nang x)) hoi. hieu ve tham thuc van hanh doi cua tre.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (doc sach)) ly ((dang xay) or (nang x)) hoi. hieu ve tham thuc van hanh doi cua tre*.