Perhaps you should try some spelling variations:
tham thuc » nham thuc, pham thuc, tam thuc
hang tai » hang va, dung tai
vat danh » va danh, van danh, luat danh
danh vi » hanh vi, dinh vi, danh di
ve tham » va tham, ve cham, vi tham
hieu ve » hieu va, hieu van
tai hai » thi hai, dai hai, tai ha
sach ky » sach ty, sach kem, sach hay
sac ky » cac ky, sai ky
vi cua » vai cua, di cua
cua te » cua tu

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

• Performing a fuzzy search may retrieve terms with similar spellings: su ((((sach ky) or (sach y))) or (sac ky)) hang tai hai. hieu ve tham thuc vat danh vi cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((((sach ky) OR (sach y))) OR (sac ky)) hang tai hai. hieu ve tham thuc vat danh vi cua te.
• Adding a wildcard symbol may retrieve word variants: su ((((sach ky) or (sach y))) or (sac ky)) hang tai hai. hieu ve tham thuc vat danh vi cua te*.