Perhaps you should try some spelling variations:
thien van » thi van
cau thuc » cuu thuc, can thuc, cau phuc
dua tren » dung tren
ly nang » ky nang, ly hang, ly vang
nang ma » tang ma, sang ma, nang cao
so sach » so sanh, bo sach, co sach
dan hai » doan hai, dang hai, dan khai
hai dua » hai cua, dai dua, hai qua
su sach » vu sach
ma hoi » mai hoi, xa hoi, ma hoa
va dan » ca dan, va dao, va dau

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) or (so sach)) ly nang ma hoi. thien van ((cau thuc) OR (cau truc)) va dan hai dua tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((su sach) OR (so sach)) ly nang ma hoi. thien van ((cau thuc) OR (cau truc)) va dan hai dua tren*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((su sach) or (so sach)) ly nang ma hoi. thien van ((cau thuc) OR (cau truc)) va dan hai dua tren*".