Perhaps you should try some spelling variations:
vat hanh » vat thanh, van hanh, va hanh
lang hoa » hang hoa, nang hoa, hoang hoa
hanh va » hang va, hanh vi
thu vat » thuc vat, thu va, thuat vat
hieu he » hieu ve, hiem he, hieu le
lang ha » long ha
su tien » su kien, su hien, tu tieng
sach ty » sach tu, sach thu, xach tay
he nam » ha nam, nghe 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 ty) or (sach y)) ((lang hoa) OR (lang ha)) doi. hieu he nam thu vat hanh va su tien~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ty) OR (sach y)) ((lang hoa) OR (lang ha)) doi. hieu he nam thu vat hanh va su tien*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ty) or (sach y)) ((lang hoa) OR (lang ha)) doi. hieu he nam thu vat hanh va su tien*".