Perhaps you should try some spelling variations:
thanh dan » thanh san, thanh van, 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
thuc va » thuc vat, thuc dan, thuc day
nang ho » nang hoc, nang co, tang ho
hieu ve » hieu va, hieu van
ho hoc » hoa hoc, cho hoc, hoi hoc
dan su » dang 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 ho hoc. ((hieu ve) or (lieu va)) am thuc va thanh dan su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky nang ho hoc. ((hieu ve) OR (lieu va)) am thuc va thanh dan su triet.
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (toc sach)) ky nang ho hoc. ((hieu ve) or (lieu va)) am thuc va thanh dan su triet*.