Perhaps you should try some spelling variations:
su triet » su tien, ve triet
vat hanh » vat thanh, van hanh, va hanh
lang hoa » hang hoa, lang ha, nang hoa
tu sach » thu sach, su sach, tu cach
hanh va » hang va, hanh vi
thu vat » thuc vat, thu va, thuat vat
hieu ve » hieu va, hieu van
hoa doi » hoa dai, hoc doi, xoa doi
ky lang » ky nang, ky dang, ky tang
te sach » toc sach
su viet » so viet
ve nam » he nam, va nam, le nam

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