Perhaps you should try some spelling variations:
su triet » su viet, su tien, ve triet
nang hoa » nang hoat, nang hoc, nang ho
vat hanh » vat thanh, van hanh, va hanh
hang hoa » hang khoa, thanh hoa, hang va
toc sach » hoc sach, doc sach, thuoc sach
hieu va » lieu va, hieu qua
thu vat » thuc vat, thu va, thuat vat
hanh va » hang va, hanh vi
tu sach » thu sach, su sach, te sach
va nam » van nam, ha nam, va nay

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

• Performing a fuzzy search may retrieve terms with similar spellings: ((tu sach) or (toc sach)) ky ((nang hoa) OR (hang hoa)) doi. hieu va nam thu vat hanh va su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (toc sach)) ky ((nang hoa) OR (hang hoa)) doi. hieu va nam thu vat hanh va su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (toc sach)) ky ((nang hoa) OR (hang hoa)) doi. hieu va nam thu vat hanh va su triet".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (toc sach)) ky ((nang hoa) OR (hang hoa)) doi. hieu va nam thu vat hanh va su triet*.