Perhaps you should try some spelling variations:
sach ky » sach y, sach ty, sach kem
hieu va » lieu va, hieu qua
xuc van » luc van, vuc van, xuc ban
duc van » duc va, duc tan, duc manh
ban tai » van tai, han tai, ban thi
cuc tre » duc tre, cua tre, cuu tre
sac ky » cac ky, sai ky
nang o » nang co, nang ho, nang ro
va hau » van hau, va chau, vat hau
o hai » co hai, so hai, o lai

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 o hai. hieu va hau ((xuc van) OR (duc van)) ban tai cuc tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu ((sach ky) OR (sac ky)) nang o hai. hieu va hau ((xuc van) OR (duc van)) ban tai cuc tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu ((sach ky) or (sac ky)) nang o hai. hieu va hau ((xuc van) OR (duc van)) ban tai cuc tre".
• Adding a wildcard symbol may retrieve word variants: tu ((sach ky) or (sac ky)) nang o hai. hieu va hau ((xuc van) OR (duc van)) ban tai cuc tre*.