Perhaps you should try some spelling variations:
ve triet » va trien, su triet
van hanh » van thanh, ban hanh, van anh
thuc van » thuc vat, thuc dan, thuc va
lang hoa » hang hoa, lang ha, nang hoa
hanh ve » hanh vi, hanh va, hanh kem
sach ky » sac ky, sach ty, sach kem
hoa hoi » khoa hoi, hoa hoc, hoa doi
le nam » he nam, le na, te nam
ve ve » de ve, va ve, ke ve

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