Perhaps you should try some spelling variations:
thanh dai » thanh hai, thanh tai, thanh dat
su triet » su viet, su tien, ve triet
toc sach » hoc sach, doc sach, thuoc sach
va thanh » gia thanh, ban thanh, va tinh
hieu van » hieu va, thien van, lieu va
thuc va » thuc vat, thuc dan, thuc day
nang ho » nang hoc, nang co, tang ho
van am » van nam, van lam, van dam
nang o » nang co, nang ro, nang x
dai su » dai sua, dai so, dan su

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 (toc sach)) ky ((nang o) or (nang ho)) hoc. hieu van am thuc va thanh dai su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky ((nang o) OR (nang ho)) hoc. hieu van am thuc va thanh dai su triet.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky ((nang o) or (nang ho)) hoc. hieu van am thuc va thanh dai su triet*.