Perhaps you should try some spelling variations:
vat thanh » dat thanh, gat thanh, tat thanh
vat hanh » van hanh, va hanh, nhat hanh
nam thuc » nam thuoc, am thuc, nam thu
sach ky » sach y, sach ty, sach kem
cuu tre » cua tre, cau tren, cau treo
hieu va » lieu va, hieu qua
sac ky » cac ky, sai ky
vi cuu » vi luu, vinh cuu
va nam » van nam, ha nam, va nay
x hoi » xa hoi, o hoi, x ho

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 (sac ky)) nang x hoi. hieu va nam thuc ((vat hanh) or (vat thanh)) vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang x hoi. hieu va nam thuc ((vat hanh) OR (vat thanh)) vi cuu tre.
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang x hoi. hieu va nam thuc ((vat hanh) or (vat thanh)) vi cuu tre*.