Perhaps you should try some spelling variations:
thien van » thi van
hieu van » hieu va, lieu va, hieu ve
thanh da » thanh dat, thanh dam, thanh dan
cau tren » cu tren, dau tren, ca tren
so sach » so sanh, bo sach, co sach
sach ty » sach y, sach tu, sach thu
ty nang » ky nang, ty xang, ty hang
nang ma » tang ma, sang ma, nang cao
tham so » ham so, tham do, than so
ma hoi » mai hoi, xa hoi, ma hoa
so gia » so giai, so giao, ho gia
da cau » dat cau, va cau

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

• Performing a fuzzy search may retrieve terms with similar spellings: so sach ty nang ma hoi. ((hieu van) OR (thien van)) tham so gia thanh da cau tren~.
• The words AND, OR and NOT may confuse the search; try adding quotes: "so sach ty nang ma hoi. ((hieu van) OR (thien van)) tham so gia thanh da cau tren".
• Adding a wildcard symbol may retrieve word variants: so sach ty nang ma hoi. ((hieu van) OR (thien van)) tham so gia thanh da cau tren*.