Perhaps you should try some spelling variations:
thanh dat » thanh san, thanh hai, thanh van
thanh mat » thanh mau, thanh mot, thanh san
tu sach » thu sach, su sach, te sach
ve pham » vi pham, v pham, ve phan
duc van » duc va, duc tan, duc manh
hieu ve » hieu va, hieu van
nang ma » tang ma, sang ma, nang cao
ma hoi » mai hoi, xa hoi, ma hoa
cua te » cua tu

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) or (thu hoach)) ky nang ma hoi. hieu ve pham duc van ((thanh mat) OR (thanh dat)) cua te~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((tu sach) OR (thu hoach)) ky nang ma hoi. hieu ve pham duc van ((thanh mat) OR (thanh dat)) cua te.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((tu sach) or (thu hoach)) ky nang ma hoi. hieu ve pham duc van ((thanh mat) OR (thanh dat)) cua te".
• Adding a wildcard symbol may retrieve word variants: ((tu sach) or (thu hoach)) ky nang ma hoi. hieu ve pham duc van ((thanh mat) OR (thanh dat)) cua te*.