Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
thuc day » thuc dan, thuc vat
va chat » van chat, va phat, cao chat
han tai » hang tai, nhan tai, van tai
day han » dai han, day ban, day dan
ve cham » va cham, ve chat, vu cham
sach ty » sach y, sach tu, xach tay
nang xa » nang x, lang xa, nang ma
tai va » thai va, mai va, tri va
thiet » thieu

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 ty) or (sach thu)) nang xa hoi. hieu ((ve cham) or (va chat)) thuc day han tai va thiet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach ty) OR (sach thu)) nang xa hoi. hieu ((ve cham) OR (va chat)) thuc day han tai va thiet.
• Adding a wildcard symbol may retrieve word variants: su ((sach ty) or (sach thu)) nang xa hoi. hieu ((ve cham) or (va chat)) thuc day han tai va thiet*.