Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
van tuan » van quan, van ban, anh tuan
thuc van » thuc vat, thuc dan, thuc va
cam thuc » am thuc, nam thuc, cam thu
duy can » duy van
hieu ve » hieu va, hieu van
ty sang » ty xang, ty hang, duy sang
ma hoi » mai hoi, xa hoi, ma hoa
ve cam » ve cham, ve cac, va cam
vi su » va su, ve su, oi su
ki su » ky su

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

• If you are trying to use Boolean operators, they must be ALL CAPS: thuat sach ((ty sang) OR (duy can)) ma hoi. hieu ve cam thuc van tuan ((vi su) OR (ki su)) triet~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "thuat sach ((ty sang) or (duy can)) ma hoi. hieu ve cam thuc van tuan ((vi su) OR (ki su)) triet~".
• Adding a wildcard symbol may retrieve word variants: thuat sach ((ty sang) or (duy can)) ma hoi. hieu ve cam thuc van tuan ((vi su) OR (ki su)) triet*.