Perhaps you should try some spelling variations:
cay thuoc » cua thuoc, nam thuoc, va thuoc
ve triet » va trien, su triet
nam thuc » nam thuoc, am thuc, nam thu
hanh tai » thanh tai, hang tai, han tai
bang hoc » nang hoc, quang hoc, benh hoc
mang hoc » nang hoc, mang loc, quang hoc
va hanh » van hanh, va thanh, va danh
te sach » toc sach
sach ty » sach y, sach tu, sach thu
hieu le » hieu ve, hieu he, hieu ly
tai ve » tai va, tai he, tai le

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 ((bang hoc) or (mang hoc)) moi. hieu le ((nam thuc) or (cay thuoc)) va hanh tai ve triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ty ((bang hoc) OR (mang hoc)) moi. hieu le ((nam thuc) OR (cay thuoc)) va hanh tai ve triet.
• Adding a wildcard symbol may retrieve word variants: te sach ty ((bang hoc) or (mang hoc)) moi. hieu le ((nam thuc) or (cay thuoc)) va hanh tai ve triet*.